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a humming sound similar to a heavy current passing between two metal points almost in contact. The heat was sufficient to cause the smell of scorched wood and paint to be plainly perceptible.
[The observations at Springfield, as well as those at New York and Washington were communicated by Messrs. Lewis and Lovett of the New York telegraph office.]
4. Observations made at New York by J. C. Crosson, Telegraph
On the evening of Aug. 28th, at 1\ o'clock, I experienced considerable difficulty in working, on account of the variation of current. I could work south by constantly altering the adjustment of my magnets, but the magnetism on the eastern circuit was so nearly destroyed that I could do nothing. About ten o'clock I could see nothing of the Aurora in the southern hemisphere, yet the same variations of current were manifest upon the line for an hour afterward. There was during this time a very strong turning current from the east, which resembled a reversed current so much that I disconnected my battery and put on a 'ground,' but I could not then get magnetism sufficient to work a simple armature. At 12h 30,n the current from the east assumed a new feature, producing enough magnetism to work quite well, yet wavering and varying in intensity.
5. Observations made at Philadelphia, communicated by H. EmMONS Thayek, Telegraph Superintendent.
On the evening of Aug. 28th, about 8 o'clock, we lost current on all our four wires running from Philadelphia to New York, and we had strong circuit as if from a near ground connection; but there was no interruption on wires running south to Baltimore and Washington. At 9h 10m the wires were relieved to a great extent from the influence of the Aurora, giving us our usual working current.
On testing wires at 8 o'clock on the morning of Sept. 2d, I found two of our wires, those running via Camden and Amboy to New York, strongly under the influence of an Aurora. The effect was different from that of Aug. 28th. There was an intensity of current which gave a severe shock when testing, giving a reversed current, neutralizing our batteries, and destroying magnetism. On removing the batteries, we had a very strong circuit, giving powerful magnetism, but could not raise New York. On the line running from this city to Pittsburgh, the operator, Mr. Steacy, succeeded in transmitting a business message to Pittsburgh ivholly on the auroral current. The current was changeable, suddenly disappearing and returning at intervals of from five to ten minutes. The signals were distinct and the conversation lasted four or five minutes, the operators exchanging remarks as to the singularity of the phenomenon. At 9 A. M. all the wires were relieved from the effects of the Aurora, and worked well as usual.
6. Observations made at Washington, D. C, by Frederick W. EOYCE, Telegraph operator.
On the evening of Aug. 28th I had great difficulty in working the line to Kichmond, Va. It seemed as if there was a storm at Richmond. I therefore abandoned that wire, and tried to work the northern wire, but met with the same difficulty. For five or ten minutes I would have no trouble, then the current would change, and become so weak that it could hardly be felt. It would then gradually change to a 'ground' so strong that I could not lift the magnet. The Aurora disappeared at a little after 10 o'clock, after which we had no difficulty. During the auroral display, I was calling Richmond, and had one hand on the iron plate. Happening to lean towards the sounder, which is against the wall, my forehead grazed a ground wire. Immediately I received a very severe electric shock, which stunned me for an instant An old man who was sitting facing me, and but a few feet distant, said that he saw a spark of fire jump from my forehead to the sounder.
7. Observations made at Pittsburgh, Pa., communicated by E. W. Culgan, Telegraph manager. During the Aurora of Aug. 28th the intensity of the current evolved from it varied very much, being at times no stronger than an ordinary battery, and then suddenly changing the poles of the magnets it would sweep through them, charging them to their utmost capacity, and compelling a cessation of work while it continued.
On the morning of Sept. 2d, at my request the Philadelphia operator detached his battery, mine being already off. We then worked with each other at intervals as long as the auroral current continued, which varied from thirty to ninety seconds. During these working intervals we exchanged messages with much satisfaction, and we worked more steadily when the batteries were off than when they were attached.
On the night of Aug. 28th the batteries were attached, and on breaking the circuit there were seen not only sparks (that do not appear in the normal condition of a working line) but at intervals regular streams of fire, which, had they been permitted to last more than an instant, would certainly have fused the platinum points of the key, and the helices became so hot that the hand could not be kept on them. These effects could not have been produced by the batteries.
SECOND SERIES, Vot. XXIX, No. 85.—JAN.. 18C0.
ART. XIII.— On Numerical Relations existing between the Equivalent Numbers of Elementary Bodies; by M. Carey Lea, Philadelphia. Part I.
The determination of the chemical equivalents of the simple substances seems with each new approach to accuracy, to destroy more and more the numerical relations once supposed to exist between the equivalent numbers of certain series of elements nearly related to each other by their properties. If we except the series formed by oxygen, sulphur, selenium and tellurium, there probably remains none of those usually recognized in which the numerical relation is rigorously exact. Chlorine, bromine and iodine are represented by the numbers 85-5, 80 and 127, where the difference between the first and second term is 44-5, between the second and third, 47. Lithium, sodium and potassium have the numbers 6'95, 23, 39'2; difference of first and second terms, 16 05, of second and third, 16'20. Calcium, strontium and barium have 20, 43'77 and 68-6; difference of first and second, 23-77, of second and third, 24-83. It can be demonstrated that other relations exist, approaching quite as near to exactness as these, and some where the accuracy is perfect.
Few of the so-called elements present more directly marked analogies than nitrogen, phosphorus, arsenic and antimony, and the very interesting discoveries of Cahours and Hofmann respecting the phosphorus bases have shown that phosphorus stands in every respect intermediate between nitrogen and arsenic, forming compounds of the type S^HJPHCl, &c, like the nitrogen compounds as well as those of the type 3(C41I5)P02, &c, like those of the arsenic and antimony groups. These authors further observe that the equivalents of phosphorus, arsenic and antimony7 differ by nearly the same number (44 to 45), but that nitrogen does not exhibit this relation.*
Beyond the fact of the approximate equality of these two differences, the analogy has never been extended. The following considerations will show that this relation not only extends to nitrogen but may be carried with exactness to other elements.
If we form a descending arithmetical series beginning with antimony =120"3, and diminishing by a common difference of 45 (45-3 in one instance, 44 in several) we shall find that such a series does not cease with the third term, P=31, but gives for a fourth —14, the exact equivalent of nitrogen with a negative sign. The fifth term will be —59, the exact equivalent of tin, with a negative sign. The sixth will be —104, or very nearly the equivalent of lead (also with a negative sign). The seventh
* Kopp u. Will, Jahresbericht fur 1857.
—149, very nearly the double of the equivalent of arsenic, a previous terra in the same series. These results are exhibited in the following table.
Differ- Calculated Received
Sb = 120-3
P = 31
N = 14
Sn = 59
It will be seen presently that the number 164, the eleventh term in the above table, occurs also in the ascending positive series, and may represent the equivalent of a metal existing but as yet unknown.
If we examine the position occupied by antimony, arsenic, phosphorus and nitrogen in the electro-chemical scale of Berzelius we shall find that in proportion as their equivalent numbers diminish, their properties become more and more electro-negative; a corresponding change is also visible in the organic radicals which these elements are capable of forming by their union with carbon and hydrogen. The passage from the positive to the negative sign in the interval between phosphorus and nitrogen is accompanied by a marked change in the nature of the organic radicals into which these elements enter—3(C4H5)N does not possess the power of combining directly with oxvgcn, chlorine and sulphur which 3(C4H5)P, 3(C4H5)As, 3(C4H5)Sb exhibit in so high a degree. The methyl compounds show the same differences as the ethyl. Standing between nitrogen and arsenic, phosphorus is every way more closely allied to the latter of these substances, not only by the analogies of its organic radicals, but also by the polybasic nature of phosphoric acid.* Although tin and lead represent the further members of the same series in reference to their equivalent numbers, it is evident that the increase of electro-negative relations does not extend to them. Moreover bismuth, antimony, arsenic, phosphorus and nitrogen at their maximum of oxydation combine with five equivalents of oxygen and chlorine, whereas tin unites with but two of each, and lead at most with two of oxygen and one of chlorine.
Again, if we begin with phosphorus, and form an ascending series with a common difference of 44 (except in one instance), we shall find both the number 164, the double of which constituted the eleventh term of the preceding table, and also the equivalent of bismuth, the double of which formed the thirteenth term of the same table.
Di(V':r- Calculated Received
These four elements exhibit strong analogies and are all isomorphous with each other.
If, taking meroury as a starting point, we subtract the number 44 from each term to find the following one, we shall obtain the
Differ- Calculated Received
100 - - Hg=100
-32 - - Zn = 32-6
The salts of the protoxyds of the three last of these' metals are isomorphous. It may seem forced to place mercury in the same group, but its analogies with zinc are perhaps as strong as those which it exhibits with silver, next to which it has usually been classed, principally because the oxyds of both metals are reduced by heat. Mercury, like zinc, cadmium and certain other metals, is capable of replacing an atom of hydrogen in hydrid of ethyl, C4H5H, and of producing in this manner the conjugate
* See the very interesting paper of Cahours and Hofmann above referred to.