February 9, 1899] 



NA TURE 



339 



OUR BOOK SHELF. 

 The Worltts Exchanges in 189S : a Reckoner of Foreign 



and Colonial Exchanges. By John Henry Norman. 



Pp. 54. (London : Sampson Low, Marston, and Co.) 

 One of the main objects of this pamphlet is to show 

 how, by the use of the Chain Rule, the principles and 

 practice of foreign exchanges can be brought down to 

 the understanding of pupils of secondary and continu- 

 ation schools. The authoi-'s purpose is "to prove by 

 very simple arithmetical formula(w) (i) that if the world 

 possessed but one substance as its measure of value and 

 •equivalent in exchange, the world's interchanges of 

 things could be effected on the conditions of barter. 

 1(2) That there are in the trading world at the present 

 time seven different monetary and currency inter- 

 mediaries, five of which are of a vastly difterent nature. 

 1(3) That these seven ditierent intermediaries produce 

 forty-two different prices of intermediaries, some of which 

 either confer a bounty or impose a ta.\ in international or 

 intercolonial exchanges of things, resulting in the unfair 

 encouragement of production of things in some countries 

 and the handicapping of industries in other districts to 

 an extent which can be measured by heavy per- 

 centages." 



Heads of English business firms have lately received 

 some pretty strong hints in the public press that they 

 are losing trade all over the world because their foreign 

 representatives will not give quotations in the currencies 

 and weights and measures which are understood in the 

 country they are trading with. .\ perusal of the present 

 pamphlet should suffice with a little practice to enable 

 any clerk to make the necessary calculations. But if 

 the multiplications and divisions required in using the 

 Chain Rule are not to be made the subject of pages of 

 long strings of meaningless figures, often ending in 

 answers ten times too great or ten times too small, far 

 more attention must be given to approximate methods of 

 working with decimals than is afforded at most of our 

 schools. In this respect our foreign competitors score, as 

 the metric system provides for them an easy introduction 

 to decimals, which latter they can master in far less time 

 than is taken by our schoolboys in floundering through 

 the British labyrinth of perches, kilderkins, nails, fathoms, 

 and pennyweights. G. H. B. 



Lecture Notes on the Theory of Electrical Measurements. 



By Prof. W. A. Anthony. Pp. 90. (New York : John 



Wiley and Sons. London : Chapman and Hall, Ltd., 



189S.) 

 In the few pages of open print which go to make up 

 this little work. Prof. Anthony gives a sketch of his course 

 of lectures on elementary measurements in electricity and 

 magnetism, in which, while enlarging upon the theoretical 

 part, he merely indicates the experimental and practical 

 part by a number of disjointed notes. 



This irregular treatment of subject-matter is quite in- 

 tentional, the aim of the book being simply that of 

 enabling the careful student to illuminate those passages 

 of his lecture notes which arc likely to be obscure. But 

 the irregularity naturally makes the book unsatisfactory 

 both for perusal and for reference. For while such a 

 work may be beneficial to a certain type of student, and 

 would doubtless be of value to students of Prof Anthony's 

 classes ; yet it may be questioned whether works of this 

 kind can with advantage be recommended to beginners, 

 or whether these would take kindly to a book in which 

 all superficially interesting matter is avoided, and the 

 uninteresting alone retained. 



The book is by no means free from misprints and other 

 slips : as " ratios " for " ratio " on p. 36 ; .r for X in the 

 equation on p. 53; again, the statement on p. 61 that 

 "the potential difference between the ends of a potentio- 

 meter slide-wire may be varied by shunting a part of its 



NO. 1528, VOL. 59] 



current away," seems to us misleading if not inaccurate. 

 The diagrams also, though few in number, are somewhat 

 open to criticism ; thus we think the forces in Kig. 3 

 should be so drawn as to represent a state of equilibrium, 

 while the figure on the succeeding page is almost un- 

 intelligible owing to the deflecting force not being drawn 

 at right angles to the needle. 



Apart, however, from such blemishes, and putting aside 

 questions of general utility, it must be conceded that the 

 matter in this little book is well arranged, and the new 

 conceptions admirably introduced ; while the deductions 

 of well-known forniuhii are in many cases very neatly 

 given. D. K. M. 



The Micro-ortranisni of Faulty Rum. By V. H. V'eley, 

 M.A., F.R.S., and Lilian J. \'eley {ni!e Gould). Pp. 

 64. ("London : Henry Frowde, 1S98.) 

 B.\CTF,Rl.\l, idiosyncrasies are now so familiar and 

 so numerous, that it is difticult for us to be taken 

 unawares any more by the whims and peculiarities 

 of these groups of lowly organisms. Mr. and Mrs. 

 \'eley have, however, succeeded in discovering an 

 oddity which, even in this remarkable community, 

 stands out in relief Whilst studying the causes 

 of faulty rum, these investigators have come upon 

 an organism which, in its lust for sugar, will brave the 

 untoward surroundings of a liquid containing over 70 per 

 cent, of alcohol. This is an unheard-of feat amongst 

 these low forms of life. To enable it to indulge in sugar 

 in such en\ironment, this organism surrounds itself with 

 a gelatinous envelojic which, whilst permitting it to 

 obtain its favourite food-stuff, protects it from the dele- 

 terious effect of the alcohol, and these characteristics 

 have been embodied in the name Coleothrix methystes 

 selected for it by its discoverers — KoXfor, a sheath, 

 fifdva-Ttji, a drunkard. Unfortunately for spirit distillers, 

 this organism elects to dwell in rum, producing, according 

 to Mr. and Mrs. \'eley, a change in the spirit which, 

 under the title of " faulty rum," occasions losses of some 

 thousands of pounds annually to manufacturers. The 

 life-history of this said Coleothrix methystes is by no 

 means an easy one to trace ; in fact, the various phases 

 through which it is said to pass embracing such trans- 

 formations as coccus to rod, coccus to filament, and fila- 

 ment to coccus forms, leave its identity still open to 

 speculation and further inquiry ; indeed, as the authors 

 themselves modestly remark, " a subject of legitimate 

 controversy." Whatever may be the results of such 

 legitimate controversy, only praise is due to the authors 

 for the conscientious care and the great labour they have 

 bestowed upon this most difficult piece of work ; and, 

 doubtless, now investigators have been started in this 

 direction, many will be stimulated to travel over the same 

 ground, and further extend our knowledge on such an 

 interesting and novel subject as the possibilities of life in 

 liquids containing such a high percentage of alcohol. 

 G. C. Frankland. 



Les Recettes du Distillateur. By Ed. Fierz. Pp. 149. 



(Paris: Gauthier-Villars, 1S99.) 

 This book contains an exposition of an art peculiarly 

 French — the preparation of liqueurs, recipes being given 

 for upwards of 150 essences. Stress is laid upon the 

 necessity for using absolutely pure materials, the quality 

 of the alcohol employed being of especial importance, 

 and tests are given for empyreumatic oils, the presence 

 of which would be particularly injurious. The alcohol 

 is aromatised by distillation or digestion with suitable 

 plants or roots, the alcohols used in the preparation of 

 some of the liqueurs requiring the addition of upwards 

 of twenty ingredients in this preliminary operation, and 

 this is then mi.xed with sugar syrup, pure alcohol, colour- 

 ing materials and essences to form the liqueur. The 

 instructions are both detailed and precise. 



