644 



SCIENCE. 



[N. S. Vol. XI. No. 278. 



ber 7, 1894, contains an account of the stage 

 the author's hydrogen experiments had 

 reached at that date. The object was to 

 collect liquid hydrogen at its boiling point, 

 in an open vacuum vessel, which is a much 

 more difficult problem than seeing it in a 

 glass tube under pressure and at a higher 

 temperature. In order to raise the critical 

 point of hydrogen to about — 210°, from 2 

 to 5 per cent, of nitrogen or air was mixed 

 with it. This is simply making an artificial 

 gas containing a large proportion of hydrogen 

 which is capable of liquefaction by the use of 

 liquid air. The results are summed up in 

 the following extract from the paper ; 

 " One thing can, however, be proved by 

 the use of the gaseous mixture of hydrogen 

 and nitrogen, namely that by subjecting it 

 to a high compression at a temperature of 

 — 200° and expanding the resulting liquid 

 into air, a much lower temperature than 

 anything that has been recorded up to the 

 present time can be reached. This is 

 proved by the fact that such a mixed gas 

 gives, under the conditions, a paste or jelly 

 of solid nitrogen, evidently giving off hy- 

 drogen, because the gas coming off burns 

 fiercely. Even when hydrogen containing 

 only some 2 to 5 per cent, of air is simi- 

 larly treated, the result is a white solid 

 matter (solid air) along with a clear liquid 

 of low density, which is so exceedingly 

 volatile that no known device for collecting 

 it has been successful." This was in all 

 probability the first liquid hydrogen ob- 

 tained, and the method is applicable to 

 other difiicultly liquefactible gases. 



Continuing the investigations during the 

 winter of 1894, and the greater part of 

 1895, the author read a paper before the 

 Chemical Society in December of that year 

 entitled, ' The Liquefaction of Air and Re- 

 search at Low Temperatures,'* in which 

 occasion was taken to describe for the first 



*' Proceedings' of the Chemical Society, No. 158, 

 1895. 



time the mode of production and use of a 

 Liquid Hydrogen Jet. At the same meet- 

 ing Professor "William Eamsay made an 

 announcement of a sensational character, 

 which amounted to stating that my hy- 

 drogen results had been not only antici- 

 pated but bettered . The statement made to 

 the Society by Professor Eamsay, reads as 

 follows : "Professor Olszeioski had succeeded in 

 liquefying hydrogen, and from unpublished in- 

 formation received from Cracoiv, he (Bamsay) 

 was able to state that a fair amount of liquid had 

 been obtained, not as a froth, but in a state of 

 quiet ebidlition, by surrounding a tube contain- 

 ing compressed hydrogen by another tube also 

 containing compressed hydrogen at the tempera- 

 ture of oxygen boiling at a very low piressure. 

 On alloiving the hydrogen in the middle jacket 

 suddenly to expand, the hydrogen in the inner- 

 most tube liquefied, and was seen to have a men- 

 iscus. Its critical point and its boiling point, 

 under atmospheric pressure, were determined by 

 means of a resistance thermometer." * 



This announcement of Professor Eam- 

 say's had from its very specific and detailed 

 experimental character the merit of the ap- 

 pearance of being genuine, although it was 

 never substantiated, either by the produc- 

 tion of the Cracow document, or by any 

 subsequent publication of such important 

 results by Professor Olszewski himself My 

 observation at the time on Professor Eam- 

 say's communication was that quotations 

 had been made in my paper from the most 

 recent publications of Professor Olszewski 

 in which he made no mention of getting 

 ' Static Hydrogen or of seeing a meniscus ' or of 

 getting what Professor Ramsay alleged ' a fair 

 amount of liquid, not as a froth, but in state of 

 quiet ebullition.' To achieve such a result 

 would require a very different scale of ex- 

 periment from anything Professor Olszewski 

 had so far described. N"aturally an early 

 corroboration of the startling statement 



* ' Proceedings ' of the Chemical Society, No. 195, 

 1897-1898. 



