SCIENCE. 



275 



John Goodricke, an English astronomer, who in 1 782 

 determined the period of the variability of the famous 

 star Algol, thought that Tycho's star might be the same 

 as the new stars reported to have been seen in the 

 years 945 and 1264. This would make the period of 

 its variability between 300 and 320 years, and hence 

 this star should re-appear in the latter part of the present 

 century. Goodricke's conjecture seems to be very un- 

 certain, since the reports for the years 945 and 1264 

 are extremely vague. It will be seen that if we as- 

 sume the period of the variability of Tycho's star to 

 be 315 years, five such periods would carry it back to 

 near the beginning of the Christian era. Astrologers 

 and others have not been slow to catch at such anal- 

 ogies, and to base predictions on these uncertain data ; 

 and thus we have it asserted that Tycho's star is iden- 

 tical with the star of Bethlehem, and that it will re-ap- 

 pear in the year 1887, with wars and social revolutions. 

 Of course it is impossible to reply to such assertions. 

 Wars and social revolutions are continually going on, 

 and such grim predictions are as safe therefore, as it 

 is to say, that to-morrow the winds will be variable, or 

 that we shall have " rain in areas ;" or snow next Jan- 

 uary. The only wonder is that intelligent people are 

 imposed on by such assertions. 



At the present time more than a hundred variable 

 stars are known to astronomers, and every year in- 

 creases their number. Many of their periods are well 

 determined, but what causes the variations of light 

 we do not know. The so-called new stars may be 

 only extreme cases of the variable stars, and the ap- 

 pearance of one is an interesting astronomical phen- 

 omenon which should be carefully observed. There 

 is a rich field for observation and for study. 



A. Hall. 



Washington, D.C., Nov. 29, li 



NEW YORK ACADEMY OF SCIENCE. 



We direct special attention to the excellent course of 

 lectures provided by the New York Academy of Sciences, 

 to which non-members are admitted free, on making 

 application to the proper authorities. 



The lecture tor Monday next, December 6th, will be 

 delivered by Professor W. Boyd Dawkins, F. R. S., of 

 Owens College, Manchester, England, the subject being 

 "The Man ot the Caves." 



We understand the present will be the only opportunity 

 for hearing Professor Dawkins lecture in this country on 

 a subject on which he is a specialist. We anticipate 

 a large attendance. 



The present efforts of the executive of the New York 

 Academy of Science, under the presidency of Professor 

 Newberry, to provide a course of free lectures of the 

 highest order, should be fully recognized by all in- 

 terested in Science and we advise those who would 

 avail themselves of the opportunity to address Professor 

 D. S. Martin, of 23S West Fourth street ; or Professors 

 W. P. Trowbridge and Alexis A. Julien, both of Colum- 

 bia College, N. Y., as these gentlemen constitute the 

 Committee on Lectures. 



HISTORICAL NOTES uN GAS ILLUMINATION. 



At the present moment when the public is all impa- 

 tience to see the electric light perfected for general illu- 

 minating purposes, it may be interesting to note a few 

 particulars descriptive of the early days of gas, when it 

 struggled into existence for the same purposes. 



In looking over a few somewhat ancient scientific pa- 

 pers I found much relating to the subject, and will now 

 reproduce these historical facts in the order in which I 

 found them. 



It appears that in the British Museum there is pre- 

 served a paper (Ascough's Cat. 4437), entitled " Experi- 

 ments Concerning the Spirit of Coals, in a Letter to the 

 Hon. Mr. Boyle, by the late Rev. James Clayton, D.D., 

 B. Mus." These experiments were undertaken by him 

 in consequence of his having observed that the gas, issu- 

 ing from certain fissures near a coal pit at Wigan, in 

 Lancashire, took fire when a burning candle was pre- 

 sented to it. He therefore distilled coal, and obtained 

 first " phlegm," afterwards a black oil, and then " an 

 inflammable spirit," which he collected in bladders. By 

 pricking these bladders he was able to ignite the gas at 

 pleasure. Hence it is evident that the discovery of the 

 carburetted hydrogen gas took place previous to the year 

 1664. 



So states a paper, No. 66, in the Philosophical Journal, 

 by Mr. John Webster, " On the Discovery of the Inflam- 

 mable Gas from Coals ;" the date of the paper is not 

 before me, but its republication, in the form I found it, 

 was in 1807. 



In the Phil, four., No. 67, the subject is again mooted 

 by a Mr. Hume, who states that in the forty-first volume of 

 the Philosophical Transactions, p. 59, is a " sheet-paper," 

 which appears to have been read before the Royal So- 

 ciety in January, 1739, as " A Letier to the Hon. Robert 

 Boyle, from the late Rev. John Clayton. D.D., in which 

 is described how the discovery originated, and also some 

 of the effects produced by this gas or ' spirit ' of coal." 



Mr. Hume further draws attention to the difference in 

 the Christian names given to Mr. Clayton, in the first 

 instance " James " and the second " John," and draws 

 the very probable conclusion that the same person is re- 

 ferred to in both papers, and states, " At any rate, the 

 merit of this discovery can be no longer claimed by any 

 living person." 



This remark was called forth on account of the public 

 papers of that day, 1808, being much taken up with the 

 proposal of a Mr. Winsor to light cities with gas. It ap- 

 pears that Mr. Edward Heard also obtained a patent in 

 June, 1806, for " Obtaining inflammable gas from pit coal, 

 in such a state that it may be burned without producing 

 any offensive smell." 



There was money in this patent, for Mr. Winsor was 

 organizing a large company, which was not to buy the 

 patent, but to pay a royalty as a license for the exclusive 

 right to make use of it. As usual in such cases there was a 

 great outcry, and the attempt was made to break down 

 the patent by asserting that the invention was not new, 

 one Nicholson taking the ground that the patent was 

 invalid, because the inflammable nature of coal gas was 

 demonstrated by "Boyle" before 1691 ; and he further 

 stated that Lord Dundonald used gas from coal to give 

 Jight many years ago, and that a Mr. Murdock also 

 put it in practice upon a large scale in 1792 and 1798, so 

 that it was absurd for Mr. Winsor to claim the inven- 

 tion for the public use of gas. 



To parry these attacks Mr. Winsor published a small 

 .pamphlet, and boldly asserted that it was true that the 

 inflammability of coal gas had been long known, but that 

 no one had purified gas, and thus made it fit for general 

 illuminating purposes, until he took out his patent in 

 1804. He also accused others, who were in the field, of 

 having obtained their knowledge from him. 



Mr. Winsor had to contend against other difficulties ; 

 for, at that date, the statute law of the realm prohibited 

 more than five persons holding a patent as joint property, 

 and it was held that as the shareholders of the proposed 

 company would share the profits, they would be joint 

 holders of the patent. To this Mr. Winsor replied that 

 he retained the patent himsell and merely sold the right 

 to use it. To show the poor prospects for gas illumina- 



