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Notes
 

1.

SOURCE:  https://todayinsci.com/A/Ampere_Andre/AmpereAndre-Quotations.htm

 "...  Either one or the other [analysis or synthesis] may be direct or indirect. [direct analysis] , [direct synthesis] , [indirect analysis] , [indirect synthesis] , 

The "direct" procedure is when the point of departure is known-direct synthesis in the elements of geometry. 
... By combining at random simple truths with each other, more complicated ones are deduced from them. 
 This is the method of discovery, the special method of inventions, contrary to popular opinion. — André-Marie Ampère

Ordinarily, logic is divided into the examination of ideas, judgments, arguments, and methods. 
 The two latter are generally reduced to "judgments"- that is, arguments are reduced to apodictic judgments [  https://en.wikipedia.org/wiki/Apodicticity  ]
 
...  [that] such and such conclusions follow from such and such premises, and method is reduced to judgments that "prescribe" the procedure that should be followed in the search for truth.
— André-Marie Ampère

The future science of government should be called “la cybernétique”.  — André-Marie Ampère [ https://fr.wikipedia.org/wiki/Cybern%C3%A9tique#Histoire_du_mouvement ]


The word “electromagnetic” which is used to characterize the phenomena produced by the conducting wires of the voltaic pile
… were those which M. Oersted discovered, exhibited by an electric current and a magnet.   [ https://en.wikipedia.org/wiki/Hans_Christian_%C3%98rsted,    https://en.wikipedia.org/wiki/Oersted
... 
I have determined to use the word electrodynamic - in order to unite (under a common name) all these phenomena, and particularly to designate those [phenomena] which I have observed between two voltaic conductors. 


It  [ electrodynamic ] expresses their true character, that of being produced by electricity in motion: 
 while the electric attractions and repulsions, which have been known for a long time, 
 are electrostatic phenomena produced by the unequal distribution of electricity at rest in the bodies in which they are observed. — André-Marie Ampère ..." 


2.

To avoid any confusion as to the poles of the magnet, I shall designate the pole pointing to the north as the marked pole;
 I may occasionally speak of the "north and south ends of the needle", but do not mean thereby north and south poles. [ of the earth ]
 That is, by many considered the true north pole of a needle which points to the south;
but in this country [ England ] it in often called the south pole. [ https://gisgeography.com/magnetic-north-vs-geographic-true-pole/ ]

https://ece.northeastern.edu/fac-ece/nian/mom/work.html#:~:text=Magnets%20have%20two%20poles%2C%20a,end%20at%20the%20south%20pole.&text=When%20most%20people%20think%20of,force%20experienced%20between%20two%20magnets.


3. A soft iron bar in the form of a lifter to a horse-shoe magnet, when supplied with a coil of this kind round the middle of it, becomes, by juxta-position with a magnet, a ready source of a brief but determinate current of electricity.

4.  ... For a mode of obtaining the spark from the common magnet which I have found effectual, see the Philosophical Magazine for June 1832, p. 5.
 In the same Journal [ https://en.wikipedia.org/wiki/Philosophical_Magazine ] for November 1834, vol. v. p. 349, will be found a method of obtaining the magneto-electric spark, still simpler in its principle,
  the use of soft iron being dispensed with altogether.—Dec. 1838.

  - https://www.jstor.org/stable/41133982?seq=1 ::  TITLE:  "Faraday's Initial Mistake Concerning the Direction of Induced Currents ..."

 - https://onlinebooks.library.upenn.edu/webbin/serial?id=philosmag   > get other JUNE 1832 "The Philosophical Magazine"

   SOURCE: https://archive.org/details/s02philosophicalmag11londuoft   

      https://archive.org/details/s02philosophicalmag11londuoft/page/n7/mode/2up

        https://archive.org/details/s02philosophicalmag11londuoft/page/46/mode/2up?q=Faraday  < 37 instances  [ 35+ CAPTURES OF FARADAY JUNE 1832 PUBLICATIONS


5.

For important additional phenomena and developments of the induction of electrical currents, see now the ninth series, 1048-1118.—Dec. 1838. ( BY FARADAY )


6.

This section having been read at the Royal Society and reported upon, and having also, in consequence of a letter from myself to M. Hachette, been noticed at the French Institute, I feel bound to let it stand as part of the paper; but later investigations (intimated 73. 76. 77.) of the laws governing those phenomena, induce me to think that the latter can be fully explained without admitting the electro-tonic state. My views on this point will appear in the second series of these researches.—M.F.


7.

Philosophical Transactions, 1801, p. 247. ::   

[ "Philosophical Transactions" ::  https://en.wikipedia.org/wiki/Philosophical_Transactions_of_the_Royal_Society   ]

SOURCE: https://archive.org/details/s02philosophicalmag11londuoft   :::   https://archive.org/details/s02philosophicalmag11londuoft/page/  ::   "Faraday" "Philosophical Transactions" "1801", p. "247" Note 7


8.

Annales de Chimie, xxxviii. 5.    [ "Annales de Chimie" :: https://en.wikipedia.org/wiki/Annales_de_chimie_et_de_physique  ]

9.

Ibid. xxviii. 190.

10.

Ibid. xxxviii. 49.

11.

The Lycée, No. 36, for January 1st, has a long and rather premature article, in which it endeavours to show anticipations by French philosophers of my researches.

It however mistakes the erroneous results of MM. Fresnel and Ampère for true ones, and then imagines my true results are like those erroneous ones. I notice it here, however, for the purpose of doing honour to Fresnel in a much higher degree than would have been merited by a feeble anticipation of the present investigations. That great philosopher, at the same time with myself and fifty other persons, made experiments which the present paper proves could give no expected result. He was deceived for the moment, and published his imaginary success; but on more carefully repeating his trials, he could find no proof of their accuracy; and, in the high and pure philosophic desire to remove error as well as discover truth, he recanted his first statement. The example of Berzelius regarding the first Thorina is another instance of this fine feeling; and as occasions are not rare, it would be to the dignity of science if such examples were more frequently followed.—February 10th, 1832.

12.

Philosophical Transactions, 1825, p. 467.

13.

By magnetic curves, I mean the lines of magnetic forces, however modified by the juxtaposition of poles, which would be depicted by iron filings; or those to which a very small magnetic needle would form a tangent.

14.

Quarterly Journal of Science, vol. xii. pp. 74. 186. 416. 283.

15.

Philosophical Transactions, 1825, p. 481.

16.

This experiment has actually been made by Mr. Christie, with the results here described, and is recorded in the Philosophical Transactions for 1827, p. 82.

17.

Experiments which I have since made convince me that this particular action is always due to the electrical currents formed; and they supply a test by which it may be distinguished from the action of ordinary magnetism, or any other cause, including those which are mechanical or irregular, producing similar effects (254.)

18.

Philosophical Transactions, 1825. p. 317.

19.

Ibid. 1825. p. 485.

20.

I have since been able to explain these differences, and prove, with several metals, that the effect is in the order of the conducting power; for I have been able to obtain, by magneto-electric induction, currents of electricity which are proportionate in strength to the conducting power of the bodies experimented with (211.).

21.

Christie, Phil. Trans. 1825, pp. 58, 347, &c. Barlow, Phil. Trans. 1825, p. 317.

22.

1830. p. 399.

23.

Theoretically, even a ship or a boat when passing on the surface of the water, in northern or southern latitudes, should have currents of electricity running through it directly across the line of her motion; or if the water is flowing past the ship at anchor, similar currents should occur.

24.

Philosophical Transactions, 1831, p. 202.

25.

Philosophical Transactions, 1825, p. 472; 1831, p.78.

26.

Mr. Christie, who being appointed reporter upon this paper, had it in his hands before it was complete, felt the difficulty (202.); and to satisfy his mind, made experiments upon iron and copper with the large magnet(44.), and came to the same conclusions as I have arrived at. The two sets of experiments were perfectly independent of each other, neither of us being aware of the other's proceedings.

27.

Philosophical Transactions, 1831. p. 68.

28.

Edin. Phil. Journal, 1825, p. 124.

29.

Phil. Trans. 1779, p. 196.

30.

Annnles de Chimie, 1826, p. 62, &c.

31.

Phil. Trans. 1832, p. 282, note.

32.

Ibid. 1801, p. 434.

33.

Phil. Trans. 1892, p. 17. "Common electricity is excited upon non-conductors, and is readily carried off by conductors and imperfect conductors. Voltaic electricity is excited upon combinations of perfect and imperfect conductors, and is only transmitted by perfect conductors or imperfect conductors of the best kind. Magnetism, if it be a form of electricity, belongs only to perfect conductors; and, in its modifications, to a peculiar class of them34. Animal electricity resides only in the imperfect conductors forming the organs of living animals, &c."

34.

Dr. Ritchie has shown this is not the case. Phil. Trans. 1832, p. 294.

35.

Phil. Trans. 1832, p. 259. Dr. Davy, in making experiments on the torpedo, obtains effects the same as those produced by common and voltaic electricity, and says that in its magnetic and chemical power it does not seem to be essentially peculiar,—p. 274; but he then says, p. 275, there are other points of difference; and after referring to them, adds, "How are these differences to be explained? Do they admit of explanation similar to that advanced by Mr. Cavendish in his theory of the torpedo; or may we suppose, according to the analogy of the solar ray, that the electrical power, whether excited by the common machine, or by the voltaic battery, or by the torpedo, is not a simple power, but a combination of powers, which may occur variously associated, and produce all the varieties of electricity with which we are acquainted?"

At p. 279 of the same volume of Transactions is Dr. Ritchie's paper, from which the following are extracts: "Common electricity is diffused over the surface of the metal;—voltaic electricity exists within the metal. Free electricity is conducted over the surface of the thinnest gold leaf as effectually as over a mass of metal having the same surface;—voltaic electricity requires thickness of metal for its conduction," p. 280: and again, "The supposed analogy between common and voltaic electricity, which was so eagerly traced after the invention of the pile, completely fails in this case, which was thought to afford the most striking resemblance." p. 291.

36.

Elements of Chemical Philosophy, p. 153

37.

Elements of Chemical Philosophy, p. 154.

38.

Philosophical Transactions, 1827, p. 18. Edinburgh Transactions, 1831. Harris on a New Electrometer, &c. &c.

39.

Demonferrand's Manuel d'Electricité dynamique, p. 121.

40.

Annales de Chimie, xxxiii. p. 62.

41.

Philosophical Transactions, 1801, pp. 427, 434.

42.

Philosophical Transactions, 1801, p. 429.

43.

Nicholson's Journal, 4to. vol. I. pp. 311, 299. 349.

44.

Or even from thirty to forty.

45.

Bibliothèque Universelle, 1830, tome xlv. p. 213.

46.

Philosophical Transactions, 1831, p. 165.

47.

Annales de Chimie, l. p. 322.

48.

Ibid. li. p 77.

49.

Phil, Mag. and Annals, 1832, vol. xi. p. 405.

50.

Lond. and Edinb. Phil. Mag. and Journ., 1832, vol. i. p. 161.

51.

Ibid. 1832. vol. i. p. 441.

52.

Annales de Chimie, li, p. 77.

53.

Ibid. li. p. 72

54.

Bibliothèque Universelle, xxxvii. 15.

55.

Philosophical Transactions, 1773, p. 461.

56.

Ibid. 1775, p. 1.

57.

Ibid. 1776, p. 196.

58.

Ibid. 1829, p. 15.

59.

Ibid. 1832, p. 259.

60.

Philosophical Transactions, 1832, p. 260.

61.

Edinburgh Phil. Journal, ii. p. 249.

62.

Mr. Brayley, who referred me to those statements, and has extensive knowledge of recorded facts, is unacquainted with any further account relating to them.

63.

The term quantity in electricity is perhaps sufficiently definite as to sense; the term intensity is more difficult to define strictly. I am using the terms in their ordinary and accepted meaning.

64.

Many of the spaces in this table originally left blank may now be filled. Thus with thermo-electricity, Botto made magnets and obtained polar chemical decomposition: Antinori produced the spark; and if it has not been done before, Mr. Watkins has recently heated a wire in Harris's thermo-electrometer. In respect to animal electricity, Matteucci and Linari have obtained the spark from the torpedo, and I have recently procured it from the gymnotus: Dr. Davy has observed the heating power of the current from the torpedo. I have therefore filled up these spaces with crosses, in a different position to the others originally in the table. There remain but five spaces unmarked, two under attraction and repulsion, and three under discharge by hot air; and though these effects have not yet been obtained, it is a necessary conclusion that they must be possible, since the spark corresponding to them has been procured. For when a discharge across cold air can occur, that intensity which is the only essential additional requisite for the other effects must be present.—Dec. 13 1838.

65.

In further illustration of this subject see 855-873 in Series VII.—Dec. 1838.

66.

The great and general value of the galvanometer, as an actual measure of the electricity passing through it, either continuously or interruptedly, must be evident from a consideration of these two conclusions. As constructed by Professor Ritchie with glass threads (see Philosophical Transactions, 1830, p. 218, and Quarterly Journal of Science, New Series, vol. i. p.29.), it apparently seems to leave nothing unsupplied in its own department.

67.

Quarterly Journal of Science, New Series, vol. i. p. 33.

68.

Plymouth Transactions, page 22.

69.

Of course the heightened power of the voltaic battery was necessary to compensate for the bad conductor now interposed.

70.

Bibliothèque Universelle, xxi. p. 48.

71.

In reference to this law see further considerations at 910. 1358. 1705.—Dec. 1838.

72.

In 1801, Sir H. Davy knew that "dry nitre, caustic potash, and soda are conductors of galvanism when rendered fluid by a high degree of heat," (Journals of the Royal Institution, 1802, p. 53,) but was not aware of the general law which I have been engaged in developing. It is remarkable, that eleven years after that, he should say, "There are no fluids known except such as contain water, which are capable of being made the medium of connexion between the metal or metals of the voltaic apparatus."—Elements of Chemical Philosophy, p. 169.

73.

See a doubt on this point at 1356.—Dec. 1838.

74.

See 673, &c. &c.—Dec. 1838.

75.

In reference to this § refer to 983 in series viii., and the results connected with it.—Dec. 1838.

76.

Philosophical Transactions, 1821, p. 131.

77.

See now on this subject, 1340, 1341.—Dec. 1838.

78.

Annales de Chimie, xxi. pp. 127, 178.

79.

See now in relation to this subject, 1320—1242.—Dec. 1838.

80.

See the next series of these Experimental Researches.

81.

It is just possible that this case may, by more delicate experiment, hereafter disappear. (See now, 1340, 1341, in relation to this note.—Dec. 1838.)

82.

Refer to the note after 1047, Series viii.—Dec. 1838.

83.

I find (since making and describing these results,) from a note to Sir Humphry Davy's paper in the Philosophical Transactions, 1807, p. 31, that that philosopher, in repeating Wollaston's experiment of the decomposition of water by common electricity (327. 330.) used an arrangement somewhat like some of those I have described. He immersed a guarded platina point connected with the machine in distilled water, and dissipated the electricity from the water into the air by moistened filaments of cotton. In this way he states that he obtained oxygen and hydrogen separately from each other. This experiment, had I known of it, ought to have been quoted in an earlier series of these Researches (342.); but it does not remove any of the objections I have made to the use of Wollaston's apparatus as a test of true chemical action (331.).

84.

Elements of Chemical Philosophy, p. 160, &c.

85.

Ibid. pp. 144, 145.

86.

Journal of the Royal Institution, 1802, p. 53.

87.

Philosophical Transactions, 1826, p. 406.

88.

Philosophical Transactions, 1826, p. 406.

89.

Annales de Chimie, 1806, tom, lviii. p. 64.

90.

Ibid. pp. 66, 67, also tom. lxiii. p. 20.

91.

Ibid. tom. lviii. p. 68, tom, lxiii. p. 20.

92.

Ibid. tom. lxiii. p. 34.

93.

Philosophical Transactions, 1807, pp. 29, 30.

94.

Ibid. p. 39.

95.

Ibid. p. 29.

96.

Ibid. p. 42.

97.

Ibid. p. 42.

98.

Philosophical Transactions, 1826, p. 383.

99.

Ibid. pp. 389, 407, 115.

100.

Annales de Chimie, 1807, tom. lxiii. p. 83, &c.

101.

Précis Elémentaire de Physique, 3me édition, 1824, tom. i. p. 641.

102.

Ibid. p. 637.

103.

Ibid. pp. 641, 642.

104.

Précis Elémentaire de Physique, 3me édition, 1824, tom. i. p. 636.

105.

Ibid. p, 642.

106.

Précis Elémentaire de Physique, 3me édition, 1824, tom. i. pp. 638, 642.

107.

Annales de Chimie, tom, xxviii. p. 190.

108.

Ibid. pp. 200, 202.

109.

Ibid. p. 202.

110.

Ibid. p. 201.

111.

Annales de Chimie, tom, xxviii. pp. 197, 198.

112.

Ibid. pp. 192, 199.

113.

Ibid. p. 200.

114.

Annales de Chimie, tom, xxviii. tom. li. p. 73.

115.

Philosophical Transactions, 1807, p. 42.

116.

There are certain precautions, in this and such experiments, which can only be understood and guarded against by a knowledge of the phenomena to be described in the first part of the Sixth Series of these Researches.

117.

Annales de Chimie, 1807, tom, lxiii. p. 84.

118.

Annales de Chimie, 1832, tom. li. p. 73.

119.

Annales de Chimie, 1825, tom, xxviii. pp. 197, 201.

120.

See now in relation to this subject, 1627-1645.—Dec. 1838.

121.

Thermo-electric currents are of course no exception, because when they fail to act chemically they also fail to be currents.

122.

In reference to this subject see now electrolytic induction and discharge, Series XII. ¶ viii. 1343-1351, &c.—Dec. 1838.

123.

See the note to (675.),—Dec. 1838.

124.

Even Sir Humphry Davy considered the attraction of the pole as being communicated from one particle to another of the same kind (483.).

125.

See the note to (670.).—Dec. 1838.

126.

In making this experiment, care must be taken that no substance be present that can act chemically on the gold. Although I used the metal very carefully washed, and diffused through dilute sulphuric acid, yet in the first instance I obtained gold at the negative pole, and the effect was repeated when the platina poles were changed. But on examining the clear liquor in the cell, after subsidence of the metallic gold, I found a little of that metal in solution, and a little chlorine was also present. I therefore well washed the gold which had thus been subjected to voltaic action, diffused it through other pure dilute sulphuric acid, and then found, that on subjecting it to the action of the pile, not the slightest tendency to the negative pole could be perceived.

127.

Philosophical Transactions, 1807, p. 1.

128.

Ibid. p, 24, &c.

129.

Philosophical Transactions, 1807, p. 25, &c.

130.

At 681 and 757 of Series VII, will be found corrections of the statement here made respecting sulphur and sulphuric acid. At present there is no well-ascertained fact which proves that the same body can go directly to either of the two poles at pleasure.—Dec. 1838.

131.

Refer for proof of the truth of this supposition to 748, 752, &c.—Dec. 1838.

132.

Or Voltameter.—Dec. 1838.

133.

In proof that this is the case, refer to 1038.—Dec. 1838.

134.

When heat does confer the property it is only by the destruction or dissipation of organic or other matter which had previously soiled the plate (632. 633. 634.).—Dec. 1838.

135.

The heat need not be raised so much as to make the alkali tarnish the platina, although if that effect does take place it does not prevent the ultimate action.

136.

Annales de Chimie, tom. xxiv. p. 93.

137.

Ibid. tom. xxiii. p. 440; tom. xxiv. p. 380.

138.

Ibid. tom. xxiv. p. 383.

139.

tom. xxiv. pp. 94, 95. Also Bibliothèque Universelle, tom. xxiv. p. 54.

140.

Annales de Chimie, tom. xxiii. p. 440; tom. xxiv. p, 380.

141.

Giornale di Fisica, &c., 1825, tom. viii. p. 259.

142.

pp. 138, 371.

143.

I met at Edinburgh with a case, remarkable as to its extent, of hygrometric action, assisted a little perhaps by very slight solvent power. Some turf had been well-dried by long exposure in a covered place to the atmosphere, but being then submitted to the action of a hydrostatic press, it yielded, by the mere influence of the pressure, 54 per cent. of water.

144.

Fusinieri and Bellani consider the air as forming solid concrete films in these cases.—Giornale di Fisica, tom. viii, p. 262. 1825.

145.

Philosophical Transactions, 1823, p. 161.

146.

Annales de Chimie, tom. xxiv. p. 386.

147.

Philosophical Transactions, 1825, p.440.

148.

As a curious illustration of the influence of mechanical forces over chemical affinity, I will quote the refusal of certain substances to effloresce when their surfaces are perfect, which yield immediately upon the surface being broken, If crystals of carbonate of soda, or phosphate of soda, or sulphate of soda, having no part of their surfaces broken, be preserved from external violence, they will not effloresce. I have thus retained crystals of carbonate of soda perfectly transparent and unchanged from September 1827 to January 1833; and crystals of sulphate of soda from May 1832 to the present time, November 1833. If any part of the surface were scratched or broken, then efflorescence began at that part, and covered the whole. The crystals were merely placed in evaporating basins and covered with paper.

149.

In reference to this paragraph and also 626, see a correction by Dr. C. Henry, in his valuable paper on this curious subject. Philosophical Magazine, 1835. vol. vi. p. 305.—Dec. 1838.

150.

Quarterly Journal of Science, 1819, vol. vii. p. 106.

151.

Quarterly Journal of Science, vol. xxviii. p. 74, and Edinburgh Transactions, 1831.

152.

Journal of the Royal Institution for 1831, p. 101.

153.

Refer to the note after 1047, Series VIII.—Dec. 1838.

154.

[Greek: elektron], and [Greek: -odos] a way.

155.

[Greek: ano] upwards, and [Greek: -odos] a way; the way which the sun rises.

156.

[Greek: kata] downwards, and [Greek: -odos] a way; the way which the sun sets.

157.

[Greek: elektron], and [Greek: lyo], soluo. N. Electrolyte, V. Electrolyze.

158.

[Greek: aniôn] that which goes up. (Neuter participle.)

159.

[Greek: katiôn] that which goes down.

160.

Since this paper was read, I have changed some of the terms which were first proposed, that I might employ only such as were at the same time simple in their nature, clear in their reference, and free from hypothesis.

161.

Philosophical Transactions, 1830, p. 49.

162.

With regard to solution, I have met with some reasons for supposing that it will probably disappear as a cause of transference, and intend resuming the consideration at a convenient opportunity.

163.

See now, 1340, 1341.—Dec. 1838.

164.

De la Rive.

165.

With regard to perchloride and periodide of mercury, see now 1340, 1341.—Dec. 1838.

166.

In relation to this and the three preceding paragraphs, and also 801, see Berzelius's correction of the nature of the supposed now sulphuret and oxide, Phil. Mag. 1836, vol. viii. 476: and for the probable explanation of the effects obtained with the protoxide, refer to 1340, 1341.—Dec. 1838.

167.

Philosophical Transactions, 1807, pp. 32, 39; also 1826, pp. 387, 389.

168.

For a simple table of correction for moisture, I may take the liberty of referring to my Chemical Manipulation, edition of 1830, p. 376.

169.

As early us the year 1811, Messrs. Gay-Lussac and Thénard employed chemical decomposition as a measure of the electricity of the voltaic pile. See Recherches Physico-chymiques, p. 12. The principles and precautions by which it becomes an exact measure were of course not then known.—Dec. 1838.

170.

Annales de Chimie, 1801, tom. li. p. 167.

171.

Annales de Chimie, 1804, tom. li. p. 172.

172.

Elements of Chemical Philosophy, pp. 144. 161.

173.

It is remarkable that up to 1804 it was the received opinion that the metals were reduced by the nascent hydrogen. At that date the general opinion was reversed by Hisinger and Berzelius (Annales de Chimie, 1804, tom. li. p. 174,), who stated that the metals were evolved directly by the electricity: in which opinion it appears, from that time, Davy coincided (Philosophical Transactions, 1826, p. 388).

174.

See also De la Rive, Bibliothèque Universelle, tom. xl. p. 205; or Quarterly Journal of Science, vol. xxvii. p, 407.

175.

Nicholson's Quarterly Journal, vol. iv. pp. 280, 281.

176.

Annales de Chimie, 1804, tom. li. p. 173.

177.

I have not obtained fluorine: my expectations, amounting to conviction, passed away one by one when subjected to rigorous examination; some very singular results were obtained; and to one of these I refer at 1340.—Dec. 1838.

178.

It is a very remarkable thing to see carbon and nitrogen in this case determined powerfully towards the positive surface of the voltaic battery; but it is perfectly in harmony with the theory of electro-chemical decomposition which I have advanced.

179.

Annales de Chimie, tom, xxxv. p. 113.

180.

This paragraph is subject to the corrective note now appended to paragraph 696.—Dec. 1838.

181.

I mean here by voltaic electricity, merely electricity from a most abundant source, but having very small intensity.

182.

It will often happen that the electrodes used may be of such a nature as, with the fluid in which they are immersed, to produce an electric current, either according with or opposing that of the voltaic arrangement used, and in this way, or by direct chemical action, may sadly disturb the results. Still, in the midst of all these confusing effects, the electric current, which actually passes in any direction through the body suffering decomposition, will produce its own definite electrolytic action.

183.

I have not stated the length of wire used, because I find by experiment, as would be expected in theory, that it is indifferent. The same quantity of electricity which, passed in a given time, can heat an inch of platina wire of a certain diameter red-hot, can also heat a hundred, a thousand, or any length of the same wire to the same degree, provided the cooling circumstances are the same for every part in all cases. This I have proved by the volta-electrometer. I found that whether half an inch or eight inches were retained at one constant temperature of dull redness, equal quantities of water were decomposed in equal times. When the half-inch was used, only the centre portion of wire was ignited. A fine wire may even be used as a rough but ready regulator of a voltaic current; for if it be made part of the circuit, and the larger wires communicating with it be shifted nearer to or further apart, so as to keep the portion of wire in the circuit sensibly at the same temperature, the current passing through it will be nearly uniform.

184.

Literary Gazette, 1833, March 1 and 8. Philosophical Magazine, 1833, p. 201. L'Institut, 1833, p.261.

185.

By the term voltaic pile, I mean such apparatus or arrangement of metals as up to this time have been called so, and which contain water, brine, acids, or other aqueous solutions or decomposable substances (476.), between their plates. Other kinds of electric apparatus may be hereafter invented, and I hope to construct some not belonging to the class of instruments discovered by Volta.

186.

Recent Experimental Researches, &c., 1830, p.74, &c.

187.

The experiment may be made with pure zinc, which, as chemists well know, is but slightly acted upon by dilute sulphuric acid in comparison with ordinary zinc, which during the action is subject to an infinity of voltaic actions. See De la Rive on this subject, Bibliothèque Universelle, 1830, p.391.

188.

The acid was left during a night with a small piece of unamalgamated zinc in it, for the purpose of evolving such air as might be inclined to separate, and bringing the whole into a constant state.

189.

The experiment was repeated several times with the same results.

190.

The following is a more striking mode of making the above elementary experiment. Prepare a plate of zinc, ten or twelve inches long and two inches wide, and clean it thoroughly: provide also two discs of clean platina, about one inch and a half in diameter:—dip three or four folds of bibulous paper into a strong solution of iodide of potassium, place them on the clean zinc at one end of the plate, and put on them one of the platina discs: finally dip similar folds of paper or a piece of linen cloth into a mixture of equal parts nitric acid and water, and place it at the other end of the zinc plate with the second platina disc upon it. In this state of things no change at the solution of the iodide will be perceptible; but if the two discs be connected by a platina (or any other) wire for a second or two, and then that over the iodide be raised, it will be found that the whole of the surface beneath is deeply stained with evolved iodine.—Dec. 1838.

191.

In relation to this difference and its probable cause, see considerations on inductive polarization, 1354, &c.—Dec. 1838.

192.

Refer onwards to 1705.—Dec. 1838.

193.

Wollaston, Philosophical Transactions, 1801, p. 427.

194.

I do not mean to affirm that no traces of electricity ever appear in such cases. What I mean is, that no electricity is evolved in any way, due or related to the causes which excite voltaic electricity, or proportionate to them. That which does appear occasionally is the smallest possible fraction of that which the acting matter could produce if arranged so as to act voltaically, probably not the one hundred thousandth, or even the millionth part, and is very probably altogether different in its source.

195.

It will be seen that I here agree with Sir Humphry Davy, who has experimentally supported the opinion that acids and alkalies in combining do not produce any current of electricity. Philosophical Transactions, 1826, p. 398.

196.

It will I trust be fully understood, that in these investigations I am not professing to take an account of every small, incidental, or barely possible effect, dependent upon slight disturbances of the electric fluid during chemical action, but am seeking to distinguish and identify those actions on which the power of the voltaic battery essentially depends.

197.

Elements of Chemical Philosophy, p. 149; or Philosophical Transactions, 1826, p. 403.

198.

Elements of Chemical Philosophy, p. 148.

199.

In connexion with this part of the subject refer now to Series XI. 1164, Series XII. 1343-1358, and Series XIII. 1621. &c.—Dec. 1838.

200.

When nitro-sulphuric acid is used, the spark is more powerful, but local chemical action can then commence, and proceed without requiring metallic contact.

201.

It has been universally supposed that no spark is produced on making the contact between a single pair of plates. I was led to expect one from the considerations already advanced in this paper. The wire of communication should be short; for with a long wire, circumstances strongly affecting the spark are introduced.

202.

See in relation to precautions respecting a spark, 1074.—Dec. 1838.

203.

Refer to 1738, &c. Series XIV.—Dec. 1838.

204.

Philosophical Transactions, 1807.

205.

Ibid. 1826, p. 383.

206.

Ibid. 1826, p. 389.

207.

I at one time intended to introduce here, in the form of a note, a table of reference to the papers of the different philosophers who have referred the origin of the electricity in the voltaic pile to contact, or to chemical action, or to both; but on the publication of the first volume of M. Becquerel's highly important and valuable Traité de l'Electricité et du Magnétisme, I thought it far better to refer to that work for these references, and the views held by the authors quoted. See pages 86, 91, 104, 110, 112, 117, 118, 120, 151, 152, 224, 227, 228, 232, 233, 252, 255, 257, 258, 290, &c.—July 3rd, 1834.

208.

Quarterly Journal of Science, 1831, p. 388; or Bibliothèque Universelle, 1830, p. 391.

209.

Jameson's Edinburgh Journal, October 1828.

210.

Recent Experimental Researches, p. 42, &c. Mr. Sturgeon is of course unaware of the definite production of electricity by chemical action, and is in fact quoting the experiment as the strongest argument against the chemical theory of galvanism.

211.

Philosophical Transactions, 1826, p. 405.

212.

Annales de Chimie, tom. xxviii. p 190; and Mémoires de Génève.

213.

Philosophical Transactions, 1826, p. 413.

214.

Annales de Chimie, tom. xxxiii. pp. 117, 119, &c.

215.

Journal de Physique, tom. lvii. pp. 319, 350.

216.

Philosophical Transactions, 1826, p. 113.

217.

Journal de Physique, lvii. p. 349.

218.

The gradual increase in the action of the whole fifty pairs of plates was due to the elevation of temperature in the weakly charged trough by the passage of the current, in consequence of which the exciting energies of the fluid within were increased.

219.

For further practical results relating to these points of the philosophy of the voltaic battery, see Series X. § 17. 1163.—1160.—Dec. 1838.

220.

Vol. v. pp. 349, 444.

221.

Philosophical Transactions, 1832, p. 126.

222.

Quarterly Journal of Science, vol. xii, p. 420.

223.

It was ascertained experimentally, that if a strong current was passed through the galvanometer only, and the needle restrained in one direction as above in its natural position, when the current was stopped, no vibration of the needle in the opposite direction took place.

224.

Recueil d'Observations Electro-Dynamiques, p. 285.

225.

Philosophical Transactions, 1823, p. 155.

226.

Philosophical Magazine, 1824, vol. lxiii. p. 241; or Silliman's Journal, vol. vii. See also a previous paper by Dr. Hare, Annals of Philosophy, 1821, vol. i. p. 329, in which he speaks of the non-necessity of insulation between the coppers.

227.

The papers between the coppers are, for the sake of distinctness, omitted in the figure.

228.

A single paper thus prepared could insulate the electricity of a trough of forty pairs of plates.

229.

Gay-Lussac and Thenard, Recherches Physico-Chimiques, tom. i. p. 29.

230.

Gay-Lussac and Thenard, Recherches Physico-Chimiques, tom, i. p. 20.

231.

Gay-Lussac and Thenard, Recherches Physico-Chimiques, tom. i. pp. 13, 15, 22.

232.

The word contiguous is perhaps not the best that might have been used here and elsewhere; for as particles do not touch each other it is not strictly correct. I was induced to employ it, because in its common acceptation it enabled me to state the theory plainly and with facility. By contiguous particles I mean those which are next.—Dec. 1838.

233.

I use the word dielectric to express that substance through or across which the electric forces are acting.—Dec. 1838.

234.

Mémoires de l'Académie, 1786, pp. 67. 69. 72; 1787, p. 452.

235.

Mémoires de l'Académie, 1785, p. 570.

236.

Philosophical Transactions, 1830.

237.

It can hardly be necessary for me to say here, that whatever general state the carrier ball acquired in any place where it was uninsulated and then insulated, it retained on removal from that place, notwithstanding that it might pass through other places that would have given to it, if uninsulated, a different condition.

238.

Encyclopædia Britannica, vol. vi. p. 504.

239.

Refer for the practical illustration of this statement to the supplementary note commencing 1307, &c.—Dec. 1838.

240.

Mémoires de l'Académie, 1787, pp. 452, 453.

241.

Philosophical Transactions, 1834, pp. 223, 224, 237, 244.

242.

See in relation to this point 1382. &c.—Dec. 1838.

243.

The theory of induction which I am stating does not pretend to decide whether electricity be a fluid or fluids, or a mere power or condition of recognized matter. That is a question which I may be induced to consider in the next or following series of these researches.

244.

I have traced it experimentally from a ball placed in the middle of the large cube formerly described (1173.) to the sides of the cube six feet distant, and also from the same ball placed in the middle of our large lecture-room to the walls of the room at twenty-six feet distance, the charge sustained upon the ball in these cases being solely due to induction through these distances.

245.

See now 1685. &c.—Dec. 1838.

246.

Mémoires de L'Institut, 1811, tom. xii. the first page 1, and the second paging 163.

247.

Refer to 1377, 1378, 1379, 1398.—Dec. 1838.

248.

Philosophical Transactions, 1834, p. 213.

249.

Refer for this investigation to 1680-1698.—Dec. 1838.

250.

Philosophical Transactions, 1834, p. 583.

251.

These will be examined hereafter (1348. &c.).

252.

Mémoires de l'Académie, 1785, p. 612. or Ency. Britann. First Supp. vol. i. p. 614.

253.

Philosophical Transactions, 1834, p, 212.

254.

Philosophical Transactions, 1776, p. 197.

255.

Annales de Chimie, xxi. pp. 127, 178, or Quarterly Journal of Science, xv. 145.

256.

Philosophical Transactions, 1834, p. 230

257.

Ibid. 1821, p. 431.

258.

See 1699-1708.—Dec. 1838

259.

Annales de Chimie, lviii. 60. and lxiii, 20.

260.

Bibliothèque Universelle, 1835, lix. 263. 416.

261.

Quarterly Journal, xxvii. 407. or Bibliothèque Universelle, xl. 205. Kemp says sulphurous acid is a very good conductor, Quarterly Journal, 1831, p. 613.

262.

Quarterly Journal, xxiv, 465. or Annales de Chimie, xxxv. 161.

263.

Philosophical Transactions, 1827, p. 22.

264.

Philosophical Transactions, 1834, p. 225.

265.

Philosophical Transactions, 1834, p. 225.

266.

Philosophical Transactions, 1834, p.229.

267.

Philosophical Transactions, 1834, p. 237, 244.

268.

Philosophical Transactions, 1834, p. 230

269.

See Harris on proposed particular meaning of these terms, Philosophical Transactions, 1834, p. 222.

270.

Encyclopædia Britannica, Supplement, vol. iv. Article Electricity, pp. 76, 81. &c.

271.

Bib. Univ. 1831, xlviii. 375.

272.

The drawing is to a scale of 1/6.

273.

Similar experiments in different gases are described at 1507. 1508.—Dec. 1838.

274.

Nautical Magazine, 1834, p 229.

275.

Bibliothèque Universelle, 1835, lix. 275.

276.

Philosophical Transactions, 1834, pp. 227, 229.

277.

See further investigations of this subject, 1658-1666. 1709-1735.—Dec. 1838.

278.

Philosophical Transactions, 1834, pp. 584, 585.

279.

See Van Marum's description of the Teylerian machine, vol. i. p. 112, and vol. ii. p. 196; also Ency. Britan., vol. vi., Article Electricity, pp. 505, 507.

280.

Van Marum says they are about four times as large in hydrogen as in air. vol. i. p. 122.

281.

Leslie. Cambridge Phil. Transactions, 267.

282.

Philosophical Transactions, 1834, p. 586.

283.

Philosophical Transactions, 1834, pp. 581, 585.

284.

Philosophical Transactions, 1836, pp. 586, 590.

285.

Description of the Teylerian machine, vol. i. pp. 28. 32.; vol. ii. p. 226, &c.

286.

Philosophical Transactions, 1834, p. 213.

287.

Exception must, of course, be made of those cases where the root of the brush, becoming a spark, causes a little diffusion or even decomposition of the matter there, and so gains more or less of a particular colour at that part.

288.

For similar experiments on different gases, see 1518.—Dec. 1838.

289.

For similar experiments in different gases, see 1510-1517.—Dec. 1838.

290.

A very excellent mode of examining the relation of small positive and negative surfaces would be by the use of drops of gum water, solutions, or other liquids. See onwards (1581. 1593.).

291.

Bibliothèque Universelle, 1836, September, p. 152.

292.

Philosophical Transactions, 1838, p. 47.

293.

See Professor Johnson's experiments. Silliman's Journal, xxv. p. 57.

294.

By spark current I mean one passing in a series of spark between the conductor of the machine and the apparatus: by a continuous current one that passes through metallic conductors, and in that respect without interruption at the same place.

295.

I cannot resist referring here by a note to Biot's philosophical view of the nature of the light of the electric discharge, Annales de Chimie, liii. p. 321.

296.

Philosophical Transactions, 1823, p. 155.

297.

Bibliothèque Universelle, xxi, 417.

298.

In the experiments at the Royal Institution, Sir H. Davy used, I think, 500 or 600 pairs of plates. Those at the London Institution were made with the apparatus of Mr. Pepys (consisting of an enormous single pair of plates), described in the Philosophical Transactions for 1832, p. 187.

299.

Philosophical Transactions, 1785, p. 272

300.

Ibid. 1822, p. 64.

301.

If a metallic vessel three or four inches deep, containing oil of turpentine, be insulated and electrified, and a rod with a ball (an inch or more in diameter) at the end have the ball immersed in the fluid whilst the end is held in the hand, the mechanical force generated when the ball is moved to and from the sides of the vessel will soon be evident to the experimenter.

302.

See De la Rive's Researches, Bib. Universelle, 1829, xl. p. 40.

303.

Amongst others, Davy, Philosophical Transactions, 1821, p. 438. Pelletier's important results, Annales de Chimie, 1834, lvi. p. 371. and Becquerel's non-heating current, Bib. Universelle, 1835, lx. 218.

304.

Philosophical Transactions, 1824, pp. 225. 228.

305.

Annales de Chimie, 1836, lxii. 177.

306.

Bib. Universelle, 1829, xl. 49; and Ritchie, Phil. Trans. 1832. p. 296.

307.

Silliman's Journal, 1834, xxv. p. 57.

308.

Thomson on Heat and Electricity, p. 171.

309.

Erman, Annales de Chimie, 1807. lxi. p. 115. Davy's Elements, p. 168. Biot, Ency. Brit. Supp, iv. p. 444. Becquerel, Traité, i. p. 167. De la Rive, Bib. Univ. 1837. vii. 392.

310.

Erman, Annales de Chimie, 1824. xxv. 278. Becquerel, Ibid. xxxvi. p. 329

311.

Becquerel, Annales de Chimie, 1831. xlvi. p. 283.

312.

Andrews, Philosophical Magazine, 1836. ix. 182.

313.

Schweigger's Jahrbuch de Chimie, &c. 1830. Heft 8. Not understanding German, it is with extreme regret I confess I have not access, and cannot do justice, to the many most valuable papers in experimental electricity published in that language. I take this opportunity also of stating another circumstance which occasions me great trouble, and, as I find by experience, may make, me seemingly regardless of the labours of others:—it is a gradual loss of memory for some years past; and now, often when I read a memoir, I remember that I have seen it before, and would have rejoiced if at the right time I could have recollected and referred to it in the progress of my own papers.—M.F.

314.

See also Hare in Silliman's Journal, 1833. xxiv. 246.

315.

Bibliothèque Universelle, 1837, vii. 388.

316.

I am glad to refer here to the results obtained by Mr. Christie with magneto-electricity, Philosophical Transactions, 1833, p. 113 note. As regards the current in a wire, they confirm everything that I am contending for.

317.

Annals of Philosophy, 1816. viii. p. 75.

318.

Annales de Chimie, 1835. xxviii. p. 196.

319.

Annales de Chimie, 1832, xlix. p. 423.

320.

Vol. iv. p. 192, 197.

321.

Traité de l'Electricité, i. p. 285.

322.

Philosophical Transactions, 1748.

323.

Ibid. 1834, p. 583.

324.

Becquerel, Traité de l'Electricité, v. p. 278.

325.

Philosophical Transactions, 1834, p. 589.

326.

Philosophical Transactions, 1821, p. 426.

327.

Ibid. 1832, p. 294.

328.

Philosophical Transactions, 1821, p. 427.

329.

Refer for further investigations to 1709.—1736.—Dec. 1838.

330.

See onwards 1711.—1726.—Dec. 1838.

331.

I mean by contiguous particles those which are next to each other, not that there is no space between them. See (1616.).

332.

See note to 1164.—Dec. 1838.

333.

See Annnles de Chimie, 1833, tom. li. pp. 422, 428.

334.

Philosophical Magazine, 1838, xii. 225, 315. also De la Rive's results with peroxide of manganese. Annales de Chimie, 1836, lxi. p. 40.—Dec. 1838.

335.

Philosophical Transactions, 1801, p. 427.

336.

Philosophical Transactions, 1807, p. 31.


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