342 



NATURE 



{Feb. 28, 1878 



return to its original configuration). In other words, we cannot 

 suppose energy to be conserved unless we connect the new forces 

 by so7iie fixed laws with known and already determinate physical 

 agents, and we must be content to regard the system as non- 

 conservative until the necessary physical connection is assigned 

 and introduced which will account for the free forces that we 

 have observed, and will allow us to comprehend their action 

 under the known laws of inanimate natural agency. This way 

 of dealing with the work of "external forces" on a system 

 which the new science of energy has devised, and shown to be 

 the only one which in these cases can be generally employed, has 

 perhaps contributed (but only by the unavoidable abstruseness and 

 abstractness which belong to the new science itself) to invest 

 with something of the appearance of a " phantom " and with an 

 air of mystery, the character of force, and the laws of its opera- 

 tion as they have been universally studied in mechanics. But 

 rightly regarded according to the simple principles of philoso- 

 phical consistency and progress, which the new science of energy 

 recognises in its probable extensions, there can be no doubt that 

 it will really tend to establish more clearly than before the 

 familiar notions of mechanics, and to open out fields of applica- 

 tion of the time-honoured laws of motion and of force in unfore- 

 seen directions, in which their certainty and truth will continue 

 to be felt as surely and to be described as simply now and here- 

 after, as they were in the days of Galileo and of Newton. 

 Newcastle-on-Tyne A. S. Herschel 



Faraday's " Experimental Researches " 



Mr. Silvanus P. Thompson, of Bristol, has made, in 

 Nature (vol. xvii. p. 304) an inexplicable attack upon my issue 

 of Faraday's " Experimental Researches in Electricity," 3 vols. 

 8vo. 1839-55, unwarranted by logic or facts. 



Mr. Thompson ordered my issue, which is advertised as "« 

 perfect copy " of Faraday's work, through a Bristol bookseller, 

 to whom it was charged at the trade price of 36^-. Mr. Thompson 

 declined to ratify his purchase, and there the matter should have 

 ended, as I would readily have cancelled the transaction with 

 his agent- 

 Mr. Thompson says that \profess to supply a perfect copy of 

 Faraday's "Experimental Researches," implying that my pro- 

 fessions are deceitful. I am at a loss to understand his meaning, 

 because the fact is that I can and do supply perfect copies. 



The history of the book is as follows : — Faraday's *' Experi- 

 mental Researches," 3 vols., appeared in 1839-55, in 3 vols. 

 Svo, with plates, and in course of time two of the volumes fell 

 out of print, which raised the market value of occasional copies 

 to seven and eight guineas. Availing myself of the opportunity 

 of buying from Mrs. Faraday the copyright and existing stock, I 

 completed, by facsimile reprint, a small number of copies, as is 

 plainly stated on the title-pages of vols i and 2. I alone possess 

 the right to reprint the whole or a portion of the work. 



It was at Mrs. Faraday's express wish that only such a reprint 

 has been executed, and I was further advised to that course by 

 eminent Fellows of the Royal Society. Mr. Thompson's innuendo 

 of wilful deception is an infamous slander unworthy of a man of 

 science. 



I consider I deserve the thanks of all purchasers of Faraday's 

 " Researches " for having invested my capital in the long dormant 

 copyright of this work, and having thus put it in the power of 

 students to obtain " perfect copies " at a moderate price. 



Messrs. Taylor and Francis, the printers of the former edition, 

 executed for me the reprint of the first two volumes (the stock of 

 the original third volume not having been exhausted.) The 

 original dates were preserved to show that no alterations had 

 been made, and to preclude the notion, which Mrs. Faraday 

 desired to avoid, that she had sanctioned a veritable new edition. 



After this explanation I do not doubt that Mr. Thompson will 

 see he has deceived himself, and I expect that he will apologise 

 for his ill-advised attack upon my genuine and authorised re- 

 issue, and admit that it is indeed a perfect copy of Faraday's 

 great work. Bernard Quaritch 



the theory of the mechanism of audition, its verification is a 

 matter of importance. 



Will the readers of Nature who can observe it write me 

 what are the intervals of pitch (i.e. thirds, fourths, octaves, fifths, 

 &c.) between the different tones heard together or alternating ? 



Xenos Clark 



916, Washington Street, San Francisco, Cal. 



Meteor 



Singing in the Ears 

 This consists of two or more continuous or alternating tones 

 originating within the ear, very faint and sounding like a tea- 

 kettle just beginning to boil, or a distant orchestra tuning. It is 

 heard when there is undue pressure of the circulation in the 

 head, as after long mental application, or upon hanging the 

 head downwards. To my ear these tones bear constant musical 

 relations to each other, and as the phenomenon bears directly on 



About 12.47 a.m. (Irish time) on Monday the i8th inst, I 

 observed a brilliant meteor when looking north from the south 

 side of Dublin. It resembled a bluish white ball with an 

 apparent diameter of about one-fifth that of the moon, which 

 was shining brightly at the time, and left behind it a continuous 

 yellowish luminous train. When first sighted it appeared at an 

 angular distance of about 15° from the polar star, and appeared 

 to be in the constellation of the Dragon, about midway between 

 the brilliant star of the constellation of Lyra and the polar star, 

 somewhat below the hne joining these constellations. 



Its path was apparently a line about 5" from the vertical, and 

 inclined from west towards east, and I lost sight of it when at an 

 angle of 10° with the horizon by intervening buildings. Its 

 brilliancy surpassed that of the moon, which at the time was 

 bright enough to allow of distinguishing printed characters. It 

 did not burst while in sight, and I heard no report. 



Royal College of Science, Dublin H. Hatfield 



Eucalyptus 



I have only just observed Dr. Calmy's letter in your impres- 

 sion of the 7th inst. (p. 283). The febrile attacks to which I 

 alluded in Nature (vol. xvii. p. 10) were sufficiently serious 

 to incapacitate shepherds and stockmen for anything like con- 

 tinuous work for two or three weeks, and on some days the men 

 were quite prostrated. The mosquito of which I spoke as not 

 being banished by the presence of Eucalyptus is that species of 

 Culex whose larval state is passed in water (the larvoe may even 

 be seen in rain-water collected in decayed parts of trees), and I 

 cannot call to mind a single place from which these pests were 

 absent, trees being present. No doubt they may be carried 

 many miles by the wind from their place of birth ; but the real 

 question is whether any species of gum so drains the land as to 

 banish both mosquito and malaria by drying wet soil. If so, 

 how is it that we find in Australia swamps which have existed 

 for apparently an indefinite time, and do not look in the least 

 likely to dry up, though the " blue " gum grows all round them, 

 where the mosquito is rampant and malarious fever not by any 

 means rare ? 1 entirely agree with Dr. Calmy that the mosquito 

 may be a " real danger to the rash traveller." One not acclima- 

 tised would suffer agonies among the mangrove swamps of More- 

 ton Bay. I have had my own hands so paralysed by the poison 

 that I could not close them without difficulty ; and a new arrival, 

 whom I took there on a duck-shooting expedition, was almost 

 blinded, and became seriously ill for some days, though he was 

 exposed to the attacks of the insects only a few hours. What- 

 ever may be the case in Algeria or the Campagna, no one familiar 

 with Australia will give the gum-trees there credit for having 

 banished swamps, malaria, or mosquitos. Is not the Newfound- 

 land mosquito of the pine forests to which Dr. Calmy alludes 

 bred in water? Arthur NicoLS 



February 20 



Telephone Experiments 



The following experiments with the ordinary small portable 

 telephone may interest your readers. 



Experiment i. Connect a small strip of zinc by a thin covered 

 wire.to one of the binding screws of the instrument, and connect in 

 the same way to the other binding screw a plate of metal with a 

 rough edge ; a saw does well. Place the end of the piece of 

 zinc in the mouth, or hold it between moist fingers. Take a 

 shilling between the fingers of the other hand and pass it along 

 the teeth of the saw. The sound is clearly heard in the telephone. 

 If instead of a shilling, a sovereign or a penny be used, the result 

 is much the same, but if a piece of zinc be substituted, the sound 

 in the telephone, if not lost, becomes very feeble. 



Experiment 2. With the apparatus as before, let a number of 

 persons, taking hand in hand, form a chain. At one end of this 

 chain the zinc is held, and at the other the shilling. When the 

 saw is rubbed the sound is heard in the telephone so long as the 

 hands are held, but on leaving go anywhere in the chain the 

 telephone becomes silent This experiment is successful with 



