I40 



SCIENCE. 



BOOKS RECEIVED. 



A Physical Treatise on Electricity and Mag- 

 netism. By J. E. H. Gordon, B. A., Camb., Assist- 

 ant Secretary of the British Association. In two 

 volumes. [London : Sampson Low, Marston, Searle 

 and Rivington. 1880. 



One of our correspondents calls attention to what he 

 considers a breach of privilege on the oart of a publish- 

 ing house, which affixes the date 1880 to a scientific text- 

 book which does not mention the telephone or moto- 

 graph. If this omission be a sin it is simply a sin of 

 omission ; but quite different is it in the case of Mr. J. E. 

 H. Gordon, an English compiler of a work on electricity 

 and magnetism, in two volumes, which has come to us, 

 with a flourish of trumpets, across the Atlantic. This 

 book, which gives many pages (we will not say, however, 

 too many, as the subject is an interesting one) to De La 

 Rue's beautiful experiments, and eighteen pages to Mr. 

 Crook's etherial and radiant speculations with Mr. 

 Gimingham's pretty tubes, only condescends to notice 

 the Bell telephone in one brief page, and entirely ignores 

 the existence of Edison's carbon telephone; although he 

 recognizes the principle of the latter in Hughes' micro- 

 phone, to which he gives great credit in another page. 

 Aside from the unpardonable negligence evinced in this 

 want of literary balance, which shows Mr. Gordon's in- 

 capacity as a book compiler, we here have a recurrence 

 of an indignity unworthy of an Englishman. Mr. Gor- 

 don (who is an Assistant Secretary of the British Asso- 

 ciation) knows, or ought to know, that Mr. Preece exhib- 

 ited an Edison musical telephone to the Association at 

 their Plymouth meeting in 1877 ; and also that Edison's 

 agent in London showed Mr. Hughes the carbon button 

 and its properties in a telephone, three weeks before Mr. 

 Hughes picked up the eliminated defects of the button 

 as the principle of the microphone. 



It does seem as if this ignoring the great services of 

 the American Edison is but a part of a scientific con- 

 spiracy to falsify history. Where is the tasimeter, the 

 most delicate electrical instrument for the measurement 

 ot radiant energy known to science ? Where the moto- 

 graph, that inexplicable wonder, which a telegraph com- 

 pany (more appreciative than Mr. Gordon) thought worth 

 a hundred thousand dollars, the price they offered and 

 paid for it ? Where are their descriptions to be found in 

 Mr. J. E. H. Gordon's Physical Treatise on Electricity 

 and Magnetism ? He does not deign to pen one line on 

 the subject. This is either ignorance or folly ; let Mr. 

 Gordon accept which horn of the dilemma he thinks 

 better. 



However, considering the hasty manner in which the 

 text of this book is thrown together, it can scarcely pass 

 into currency, except as a beautifully illustrated catalogue 

 of inventions and discoveries in which Mr. Gordon took 

 no part. In this compilation (without reference, let it be 

 distinctly understood, to the distinguished authors whose 

 works are woven in without decent order or proportion), 

 Mr. Edison shines by his absence. 



The book cannot yet be purchased here, as the Amer- 

 ii in buyers of the copyright are keeping it for the fall 

 trade. We regret their connection with it, for what 

 popularity can be expected, in this country, for a work on 

 electricity that ignores the existence of Henry, Morse 

 and Edison ? 



Manual of Hydraulic Mining for the use of 

 1 hi. I'i: \< in al Miner. By T. F. Van Wa 

 L. M., New York, I). Van Nostrand. 1880. 



Of all Ihe problems presented to the mining engineer, 



is none more important, nor simpler, than that con- 

 tained in the subject of hydraulic mining of gold. It is 

 only necessary to be sure of the premises and the results 



may be considered certain. There are, really, but two 

 questions involved, water to move the soil, and place to put 

 it in. If these conditions are fulfilled, it is not difficult to 

 predict success to those who have but fair promise of 

 paying ground. Once we know where is the dump- 

 ing ground, how high the fall, and what the grade 

 at command for sluicing boxes, all that has to be done is 

 to bring water to the highest point above the workings ; 

 which, of course, presupposes it has been lead from the 

 source to the place of fall on the least grade consistent 

 with a sure and economical supply. 



Much of the brain and sinew of the working classes 

 in the far West has taken to this class of mining, as 

 offering the most enduring profit and employment ; 

 but hydraulic mining requires something else besides 

 mere will and muscle. For its successful application 

 a certain knowledge of figures, rather than oi miner- 

 alogy, is requisite. These hardy men do not always 

 possess such knowledge, and for their instruction, Mr. 

 Van Wagenen has written a little manual which w 11 

 be read, studied and understood by many a practica' 

 miner. 



The book can serve as a model for writers who have 

 something valuable to say, and who wish to speak to 

 men who have no desire to waste tir.._ i 1 hunting for the 

 truth. 



PHYSICAL NOTES. 



The new electro-dynamic law of Clausius is receiving the 

 deepest attention from the first electricians and mathema- 

 ticians of Europe. The fundamental character of all his 

 work and the acknowledged preeminence of his views, imme- 

 diately demand an early investigation at the hands of his 

 compeers. Already have Lorberg, Delsaulx, Frolich and, 

 others submitted this law to rigid analysis. 



This new law of Clausius was advanced by the distin- 

 guished author only after finding himself unable to reconcile 

 the two laws of Weber and Rieman with that simplicity which 

 overwhelmingly addresses itself to our reason ; and because 

 they seem too complicated to be used as explanatory of these 

 molecular currents so felicitously employed by Ampere in 

 his theory of magnetism. These laws of Rieman and Weber 

 require us to believe in the existence of two equal and oppo- 

 site currents as originating all electrical action. In anothei 

 essential point, Clausius (Annalen der Physic und Chemic 

 X., 4, p. 609), finds himself compelled to differ from Rieman 

 and Weber. They assume a relative motion between the 

 electrified particles. Rieman using the word in its ordinary 

 acceptation, according to which the difference of the compo- 

 nents of velocity of the two electrical particles is made to 

 represent the components of velocity of the relative motion ; 

 and Weber referring the relative motion to the mutual ad- 

 vance and retreat of the particles. Clausius rejects this 

 method, which would confine one in the consideration of 

 the subject to relative motion, and treats of both individual 

 motions of the particles in their action on each other. 



In the same number of the Annalen is an article by Ilerr 

 Budde, on the laws of Clausius, in which, as an adherent of 

 the theory, he exposes the fallacy of Frolich's interpretation. 



THE contrary effects of sunlight in relation to certain 

 chemical compounds, is noted by T. P. Blunt {Analyst, 

 1880, 79-S1), who finds that an oxalic acid solution exposed 

 to the light is rapidly decomposed, which is not the case in 

 the dark. It this observation of Mr. Blunt is substantiated 

 the use of that valuable re-agent in stoichiometry, where it 

 serves as a basis lor standardizing, will have to be re- 

 stricted. From the ease with which oxalic acid is dried 

 and weighed, and its non-corrosive nature, it has been con- 

 sidered almost invaluable in the working laboratory. 



Mr. Blunt, on the other hand, finds that ferrous iodide 

 requires the light in order to prevent decomposition. 

 Does not this anomalous action of light point to a mechan- 

 ical association and dissociation of molecules, analagous to 

 that separation of tangible bodies effected by sound, as 

 seen in Chladni figures? 



