272 



NATURE 



[May 6, 1909 



the illustrations are excellent. Lillie's " Develop- 

 ment of the Chick " is, indeed, one of the hand- 

 somest books available for embryological study, and 

 it will be indispensable in every laboratory, though we 

 should not care to regard it as a text-book of em- 

 bryology for the student in quest of the scientific 

 principles underlying animal development. B. 



MODERN EXPLOSIVES. 

 The Manufacture of Explosives. Twenty Years' Pro- 

 gress. Four Cantor Lectures delivered at the 

 Royal Society of Arts in November and December, 

 1908, by Oscar Guttmann. Pp. viii-(-84. (Lon- 

 don : Whittaker and Co., 1909.) Price 3^. net. 

 IT is now fourteen years since Prof. V. B. Lewes 

 gave a series of Cantor lectures at the Royal 

 'Society of Arts on " Modern Explosives." The 

 period which has elapsed has been so fruitful in 

 -research and manufacturing improvements that the 

 series of lectures delivered by Mr. Guttmann, which 

 form the subject of the present volume, is very 

 welcome. 



Mr. Guttmann's treatise on " The Manufacture of 

 Modern Explosives " was published in 1895, and the 

 present small volume is a useful addendum to the 

 larger work. As is pointed out in the preface, it is 

 impossible in so small a compass to give more than 

 a general outline of the many improvements and 

 researches during the past twenty years, but this 

 •outline is certainly valuable, especially as the author 

 ■gives full references to all important patents and 

 papers. 



In spite of all advances, it is of interest to note 

 that black powder was employed in mines and quar- 

 ries to the extent of 7000 tons in 1907. In addition, 

 nearly 3500 tons of " safety " explosives were also 

 used. The world's annual production of celluloid is 

 put at the enormous total of 24,000 tons, whilst arti- 

 ficial silk reached the astonishing total of 5000 tons. 



Nitro-cotton in some form or other is, without 

 -doubt, the most important explosive compound at 

 :present made, not only because it forms the basis 

 of all smokeless propellant explosives, but also of 

 celluloid and artificial silk. No possible pains must 

 be spared to ensure stability of the nitro-cotton, and 

 the causes which may give rise to instability or pro- 

 mote further decomposition are well treated by the 

 author, but many will differ from him as to the 

 extent of deterioration arising from the preliminary 

 treatment of the cotton and the effect of alkaline 

 stabilisers. It will be admitted that nitro-cotton has 

 its defects, but such statements as " picric acid is a 

 treacherous substance," "a more inconvenient 

 material still is nitro-cotton," " we have an almost 

 uncontrollable substance in nitro-cotton," are open 

 to criticism. Later the author himself says that the 

 stability of nitro-cotton below 20° C. is assured. 



So far as our Navy is concerned, exception must 

 be taken to the statement that " it was and still is 

 the practice in men-of-war to arrange the ammuni- 

 tion stores and powder magazines in close proximity 

 to boilers and engines, frequently without any ventila- 

 NO. 2062, VOL. 80] 



tion." This has never been our practice; there have 

 been unavoidable instances where such an arrange- 

 ment has been forced upon designers by other con- 

 siderations, but in such cases the magazines have been 

 thoroughly heat-insulated. Moreover, magazines have 

 always been specially ventilated independently of the 

 general ventilation of the ship. It is fully recognised 

 by those responsible for the designs that the lower 

 the temperature the better preserved will be the 

 powder, and for that reason refrigerating machinery 

 has been introduced, but the author's fear as to 

 possible breakdown at a critical moment has not been 

 left unprovided for by men who can evolve such an 

 engine of destruction as a modern battleship. 



One turns hopefully to the question, " What will 

 be the powder of the future? " only to find that 

 " the future belongs to a stable nitro-compound of 

 the aromatic series." Possibly; but is there even 

 remote promise of the production of any such body 

 which will meet the varied requirements of a smoke- 

 less propellant as distinct from a simple explosive 

 substance? J. S. S. B. 



CHEMICAL ANALYSIS FOR STEEL-WORKS' 

 LABOR.ATORIES. 



Rapid Methods for the Chemical Analysis of Special 

 Steels, Steel-making Alloys, and Graphite. By 

 C M. Johnson. Pp. vi + 221. (New York: John 

 Wiley and Sons; London: Chapman and Hall, 

 Ltd., 1909.) Price 12s. 6d. net. 



THE author of this book gives a detailed account 

 of his methods for the determination of 

 chromium, vanadium, copper, titanium, nickel, 

 molybdenum, and tungsten in steel and steel-making 

 alloys, besides those for the ordinarily occurring 

 elements, viz. carbon, silicon, sulphur, phosphorus, 

 and manganese. No reference is made to tantalum 

 and uranium. 



Most of the methods described are to be found in 

 the standard English works on the subject, but there 

 are several new features which deserve to procure a 

 place for the book in all steel-works' laboratories. 

 Of these features, the exact determination of phos- 

 phorus in ferro-vanadium, and the application of 

 potassium ferricyanide to the separation of small 

 amounts of copper and nickel from large amounts of 

 iron are specially worthy of note. 



Many of the methods described, however, are by 

 no means " rapid," and much unnecessary time is 

 spent in fusions, washing precipitates, &c. The 

 analysis of tungsten powder is very tedious, although 

 the author supplements his methods by a well-known 

 rapid method of English origin, erroneously stated 

 by him to give low results. Again, the author fuses 

 impure tungstic oxide residues with about four times 

 the necessary amount of sodium carbonate and for 

 at least four times longer than necessary, whilst two 

 hours are required for lead molybdate to settle, 

 whereas it may be safely filtered off immediately 

 after its formation. Many other similar points might 

 be cited which are of little importance beyond the 

 fact that the author aims, as the title-page suggests, 

 at rapidity of execution. 



