3i8 



NATURE 



\_Feb. 2r, 1878 



Those who think that school education should be 

 general ; that literature, mathematics, and science should 

 share it in fair proportions ; and that entrance scholar- 

 ships at the university should be awarded to general 

 excellence, will understand how the present system dis- 

 heartens every thoughtful educator, who groans over the 

 intellectual development of his best boys distorted in 

 obedience to this tyranny of special prizes, which he 

 nevertheless must win, or forfeit his reputation as a 

 teacher. 



An exhaustive list of text-books is given by the various 

 schools. Some of them are valuable to the teacher only ; 

 others indispensable to the pupils. With very few excep- 

 tions their price is exceedingly moderate, though expen- 

 sive books such as Watts' " Dictionary of Chemistry," 

 and Weinhold's " Practical Physics," should have their 

 place in the school library as books of reference. 



It is clear that the publication of this Report marks a 

 step in advance along the path of scientific education. 

 It contains not opinions, but facts ; not theories of what 

 the teaching should be, but records of what it is ; and 

 this not scattered through the discursive pages of a Blue- 

 book, but condensed into a pamphlet of ^thirty pages. 

 Not less instructive is the comparative unanimity with 

 which different schools, swayed by independent traditions, 

 advancing on different lines, and ignorant of each other's 

 movements, have worked out the same practical results 

 and are teaching the same subjects by the same methods. 

 The problem is virtually solved ; the difficulties inherent 

 in the recasting of an ancient system have disappeared 

 so soon as they were honestly faced ; and the head- 

 masters, who perhaps looked shyly on advice from with- 

 out, will listen to it, let us hope, when recommended by 

 their colleagues. To this end the colitents of the Report 

 should be summarised, and circulated amongst the schools. 

 It would be easy for the head-masters and science-masters 

 of the schools which have answered questions to constitirte 

 an informal committee. A small working sub-committee 

 would soon formulate a scheme of science teaching, 

 based on the conclusions of the Duke of Devonshire's 

 Commission, giving accurate particulars as to methods, 

 books, tests, and cost of teaching chemistry and physics, 

 with further information on the subject of museums, 

 workshops, botanical gardens, and observatories ; and 

 this paper, drawn up in the simplest and most practical 

 shape, might be sent at once to all first-class schools with 

 the imprimatur of the entire committee. It would 

 hardly fail to gain converts amongst present schools ; 

 each new head-master, appointed, as they are appointed 

 now, with an understanding that they shall find room 

 for science in their curriculum, would hail it as of the 

 highest value ; and when compulsory legislation comes, 

 as come it must, the necessary details will all be ready to 

 its hand. W. Tuckwell 



FRANKLAND'S RESEARCHES IN 

 CHEMISTRY^ 

 Experimental Researches in Pure, Applied, and Physical 

 Chemistry. By E. Frankland, Ph.D., D.C.L., F.R.S., 

 &c. (London : Van Voorst.) 



THE section (II.) that Dr. Frankland devotes to his 

 researches in Applied Chemistry is not the least 

 interesting of the work, though the chief topics are Gas 



' Continued from p. 219. 



and Water. The author's investigation of White's process 

 for manufacturing hydrocarbon gas by passing steam 

 over red-hot coke, and carbonising the gas in the retort, 

 led to the clear distinction of the illuminating from the 

 non-illuminating constituents of the hydrocarbon gas and 

 of ordinary coal-gas. It v/as shown that marsh gas is 

 valueless as a light producer during combustion, and that 

 the luminosity of a gas flame is due to the heavier hydro- 

 carbons present, whose illuminating value can be deduced 

 from analysis and expressed in terms of olefiant gas. 

 Such an indirect method of estimating the illuminating 

 value of a sample of gas is certainly interesting, but^ it is 

 clearly unsafe ; for it involves the assumption that the 

 illuminating value is directly proportional to the per- 

 centage of a hydrocarbon mixture of unknown constitu- 

 tion, calculated somewhat empirically into equivalents of 

 the well-defined ethylene. Moreover, some recent expe- 

 riments by Dittmar seem to show that ethylene does not 

 contribute nearly so much to the luminosity of a hydrogen 

 gas flame as benzole vapour. Hydrogen containing as 

 much as lo per cent, of ethylene gave a very feebly 

 luminous flame, while hydrogen charged with only 3 per 

 cent, of benzole vapour afforded a brilliant light when 

 the gas was burned. Fortunately Dr. Frankland does 

 not wholly rely upon the method in comparing — as he 

 does in his introductory remarks on the gas investiga- 

 tions — the London supply of 1851 with that of 1876 ; for 

 he has partially employed the photometer as a check. In 

 185 1 the London gas supply contained 7*01 per cent, of 

 olefiant gas, or its equivalent of other illuminating hydro- 

 carbon, while in 1876 the percentage was 7'02. From 

 these data it was concluded that there was no difference 

 in illuminating power although the 1876 gas should be, 

 according to the Act of Parliament, four candles better 

 than that of 185 1. Dr. Frankland says : — 



" The improvement of the coal gas sold in London has 

 been only imagin^y, for no real alteration has been 

 effected. It has been made to appear better, by testing 

 it with improved burners ; but, as consumed by the 

 burners almost universally employed, it gives no more 

 light in 1876 than it did in 1851 — a conclusion which is 

 confirmed by the results of simultaneous comparative 

 trials made by Mr. Humpidge with two burners, one of 

 them similar to those by which London coal gas was 

 tested in 1851, and the other, the so-called 'gas referee's 

 burner,' at present employed in testing London coal gas. 

 At 4 P.M. on June 6, 1876, the gas supphed by the 

 Chartered Company to South Kensington Museum gave, 

 when consumed at the rate of five cubic feet per hour from 

 thei85i test-burner, a light equal to 1 1 "I standard candles, 

 and on June 28, at 3 p.m., a light equal to io'5 standard 

 candles ; but when the same gas was tested at the same 

 hours by the present referee's burner, it gave, when con- 

 sumed at the same rate, a light equal to I4"3 candles on 

 June 6, and a light equal to I4'5 candles on June 28." 



There is no doubt that the photometric determinations 

 in the above cases substantially agreed with the analytical 

 results, which latter may, in consequence, be accepted sc 

 far. The general result, however, is eminently unsatis- 

 factory to all persons interested, save the gas company. 



The second inquiry undertaken in connection with ga5 

 was that on the igniting point of coal-gas. The chief 

 facts elicited possess so much general interest that we 

 may mention them here. They were : — i. That coal-gas 

 ignites at a much lower temperature than marsh-gas, but 

 at a higher temperature than hydrogen or carbonic oxide. 



