no 



SCIENCK 



[Vol. XIV. No. 341 



Connected to it is a small pipe which supplies a current of water 

 that bathes the collodion filament, and sets it so that it can be, 

 secured by pincers and drawn out without breaking. It is after- 

 wards led to a spool', on which it is wound. 



The second apparatus, which is more complete, contains a num- 

 ber of such glass tubes, and illustrates the method by which two 

 or more filaments can be drawn out and twisted so as to form one. 

 thread. The third machine is arranged for practical work. The 

 dissolved collodion is contained in a copper receiver having a 

 capacity of about 15 litres. In this receiver it is subjected to a 

 pressure of from 8 to 10 atmospheres that forces the liquid through 

 a horizontal tube, to which are connected 72 capillary tubes, each 

 with their surrounding water-casings. In this manner 72 filaments 

 of artificial silk are produced simultaneously, and these can be spun 

 into threads of various thickness ; three such filaments being 

 twisted as a minimum, and ten as a maximum. To effect this, 

 there is placed parallel to the horizontal tube a rack carrying a 

 series of bronze blades that serve to guide the filaments. The 

 twisted threads are wound upon bobbins running on spindles 

 mounted parallel to the horizontal tube. A frame carrying as 

 many pincers as there are capillary tubes can be put in movement 

 by means of a cord, and, if any of the threads are broken, these 

 pincers take hold of the filament and join up the broken parts. 

 This apparatus is enclosed in an hermetically sealed glass case, 

 through which a current of air is continually forced by means of a 

 fan. ■ This air is warmed to assist in drying the filaments ; but it 

 becomes cool at the exit, and deposits the vapors of ether and 

 alcohol. The circulating water, which is employed to harden the 

 filaments, is discharged into a receiver. It contains a large per- 

 centage of the volatile products, which can be recovered by distilla- 

 tion, and in this way only about 20 per cent of the ether and 10 

 per cent of the alcohol are lost. One tube can produce from 3 to 

 5 pennyweight of filaments per hour, or a length of nearly if miles. 

 The apparatus works continuously, and with but little attention ; 

 and, if by any chance one of the capillary openings becomes sealed, 

 it can be cleared by applying heat. 



Under the conditions in which the machine is exhibited at work, 

 the artificial silk can be sold at from 15 francs to 20 francs the 

 kilogram, while real silk costs from 45 francs to 120 francs the 

 kilogram. The manufactured product resembles very closely the 

 natural one. It is smooth and brilliant, and the filament has a 

 strength about two-thirds that of silk. Woven into a tissue, it ap- 

 pears stronger and less liable to cut, this property being due to the 

 fact that it is not charged with destructive materials, which appear 

 to be always used in dying silk, such as zinc or lead. These foreign 

 matters are probably introduced solely for the purpose of weight- 

 ing the silk ; but there is no object for similar adulteration of the 

 artificial product, because the metallic preparations employed cost 

 as much as the collodion thread. According to M. de Chardonnet, 

 the density of his product lies between that of raw and finished 

 silk. Its resistance to a tensile strain varies from 1 5 tons to 22 

 tons per square inch (copper breaks under a load of about 18 tons, 

 and iron under 23 tons). The elasticity is about the same as that 

 of natural silk, and the inventor claims that it has a superior brillian- 

 cy. M. de Chardonnet exhibits a number of stuffs woven wholly 

 with the artificial silk, as well as others mixed with natural silk 

 and other textile materials. The results are really very remark- 

 able. Among other objects, he shows a chasuble of artificial silk 

 which will bear very close examination. 



Artificial silk is not yet manufactured on an- industrial scale, but 

 it appears that this will very shortly be done ; and, while it is 

 impossible to foretell with certainty what will be the commercial 

 results of this curious invention, it is impossible to resist the con- 

 clusion that it is highly practicable, and that it even contains the 

 elements of great future success. 



TENTH CONVENTION OF THE NATIONAL ECECTRIC- 

 LIGHT ASSOCIATION. 

 The tenth convention of the National Electric-Light Association 

 was held at Niagara Falls, N.Y., on Tuesday, Wednesday, and 

 Thursday, Aug. 6, 7, and 8, the sessions being held in the Casino. 

 The convention was called to order on Tuesday morning by Mr. 



E. R. Weeks of Kansas City, president of the association, who, in 

 his opening address, briefly outlined the objects of the meeting, and 

 gave a synopsis of the progress made in the electric -light industry 

 since the preceding convention. The address concluded with the 

 statement that statistics of the association show that the number 

 of arc lamps in service in the United States alone during the last 

 six months has increased from 219,924 to 237,017 ; that of incandes- 

 cent lamps, from 2,504,490 to 2,704,768 ; and that the number of 

 street-railroads operated by electricity is now 109, comprising 575 

 miles of track and 936 motor-cars. The capital invested in these 

 industries at present amounts to $275,000,000. 



At the conclusion of his address the president introduced the 

 Hon. W. C. Ely of Niagara Falls, who delivered the address of 

 welcome.. In his address Mr. Ely touched upon the much-talked- 

 of project of utilizing Niagara Falls as a motive power for the 

 generation of electricity on a grand scale, quoting Sir William 

 Thomson's statement that Niagara Falls possesses more power than 

 all the coal-nfines in the world, and Edison's remark that Niagara is 

 the greatest storage-battery in the worid. " This latter," Mr. Ely 

 added, " is absolutely truthful, and, with the power of the waterfall 

 developed by means of an hydraulic tunnel, a system of powerful 

 dynamos to transform the water-power into electricity, and this 

 transmitted to Buffalo, that city might be supplied with light and 

 power far more cheaply than at present, and a demonstration of 

 the capabilities of electrical power and transmission afforded that 

 would give us something more sure than the world has as yet 

 had." 



After Mr. Ely's address, the secretary read a letter from the 

 mayor of this city to the president of the association, Mr. Weeks, 

 requesting his presence at a " conference of representative citizens to 

 consider the advisability of holding an international exposition at 

 New York in 1892,' and to arrange for the preliminary work if it is 

 deemed advisable." This letter was responded to by the appointment 

 of a committee of five, whose chairman is to represent the association 

 in any manner desired by the mayor. The members of the com- 

 mittee are. Dr. Otto A. Moses of New York, chairman ; E. T. 

 Lynch, jun., of New York ; C. J. Field of Brooklyn ; Fred A. Gilbert 

 of Boston ; and J. P. Morrison of Baltimore. 



The report of the committee on the revision of the constitution 

 and by-laws was then received, printed copies of the proposed con- 

 stitution ordered distributed among the members, and its discus- 

 sion made a special business for the Thursday morning session. 

 The committee on underground conduits and conductors, being 

 called upon for its report, asked for an extension of time until the 

 next annual convention, which was granted. Mr. E. A. Foote 

 then read a paper on " The Value of Economic Data to the Electric 

 Industry," which was discussed by Messrs. Morrison, Morris, De 

 Camp, Coggeshall, and Whipple ; and a resolution based upon 

 the paper was adopted, to the effect that a committee of five be 

 appointed by the president to report at the next convention of the 

 association forms and a system of records and accounts to be kept 

 by central station companies, a system for reporting the same to 

 the association, and for comparing and publishing the data so 

 secured, for the use and benefit of the members of the association. 



Mr. M. D. Law then read a paper entitled " The Perfect Arc 

 Central Station," treating of boiler-rooms and boilers, engines, 

 shafting, dynamos, switch-board, lines, store-room, and shop. 

 This paper was discussed by Messrs. Morrison, Law, Smith, Leon- 

 ard, and De Camp. At the close of the session the president an- 

 nounced the following committee on electrical statistics : A. R. 

 Foote, chairman ; A. J. De Camp, S. A. Duncan, E. F. Peck, and 

 S. S. Leonard, assistants. 



At the Wednesday forenoon session the secretary and treasurer 

 presented their report, showing a present membership of 251, an 

 increase of 55 per cent over last year. The annual income of the 

 association is at present $5,050, and the expenses for the past six 

 months were $2,241.80. The report of the committee on har- 

 monizing electrical and insurance interests was then received and 

 adopted, and the committee continued, with instructions to take 

 under advisement the feasibility of establishing a mutual insurance 

 company. A committee was also appointed to prepare a petition 

 for the abolition of import duties on copper. At the afternoon 

 session a paper was read by Mr. F. A. Wyman, on " The Constitu- 



