SCIENCE. 



271 



LETTERS TO THE EDITOR. 



[The Editor does not hold himself responsible for opinions expressed 

 by his correspondents. No notice is taken of anonymous communi- 

 cations.'] 



To the Editor : 



It seems to me that the editorial article concerning the 

 American Society of Microscopists, which appeared in 

 " Science" on page 225, so far as it relates to what I havepre- 

 presumed to write elsewhere, is likely to place me in a false 

 position before your subscribers. I will not ask for the 

 space that would be necessary to discuss the merits of the 

 question ; suffice it to say that, with man}' others, I was in- 

 clined to regard the proposition to form a National Organi- 

 zation of Microscopists with disfavor from the first, not 

 owing to any feeling of opposition to such an organization, 

 but purely from considerations of expediency. Your re- 

 marks, however, would lead one to suppose that I had 

 made a direct criticism of the officers of the society, which 

 is not the fact. The only words I have written that could 

 possibly be construed to such a meaning, are these : "We 

 have regarded the establishment of the society as a worthy 

 experiment, but as one mainly conducted by a few leaders, 

 who had not the necessary support from microscopists 

 generally to insure its success, nor sufficient experience to 

 directly it properly." I have nothing to retract ; but if any 

 explanation is necessary, I have only to say that my language 

 was intended to apply to those who were most active in 

 forming the society in the beginning, not to the officers who 

 have since been elected. Nevertheless, to quote again from 

 my article, I wrote : " Once more we desire to say, in order 

 that no person may misunderstand us, either wilfully or 

 otherwise, that we are not moved by any spirit of opposi- 

 tion to the American Society of Microscopists." The 

 course which I strongly advocate, because it seems to me 

 that it would be beneficial to both organizations, is that the 

 American Society should disband and its members unite 

 with the A. A. A. S. It is true that this plan has met with 

 opposition from the Society, but if I read the signs aright, 

 the same resolution to do this, which was indignantly voted 

 down at Indianapolis, will be more carefully considered if 

 offered next year. 



The question that presents itself to my mind is not : Can 

 the American Society of Microscopists be made to exist as 

 an independent organization, by the efforts of a few enthu- 

 siastic members ? but it is rather : Can research with the 

 microscope be fostered better by such an organization, or 

 by the sub-section of the A. A. A. S. ? The microscope is 

 an instrument that is used in many branches of scientific 

 study, but microscopy is not the name of any science. A 

 local microscopical society may, indeed, be a centre of at- 

 traction of scientific men generally, ; but it is doubtful if a 

 national microscopal society can ever prove sufficiently at- 

 tractive to induce its members to travel half way across the 

 continent to attend its meetings. Respectfully, 

 New York, November 11, 1880. R. Hitchcock. 



To the Editor of Science : 



Vol. 1, No. 10, of the Humbolt Library, is an essay on 

 " The Theory of Sound in its Relation to Music " by Prof. 

 Pietro Blaserna, of the Royal University, of Rome. It is 

 interspersed with illustrations and demonstrations of 

 a very interesting character, and written in a popular 

 manner. 



Every musician must feel the touch of a kindred soul 

 as the subject reaches the historical phase, whilst the 

 criticisms, on national influence upon music, are very im- 

 partial and indeed beautiful. The temperate scale is 

 referred to, in too scourging a manner, which should 

 rather be applied to the dogmatic assertions of would-be- 

 musicians who have failed to acquaint themselves with 

 scientific truths. 



The essay is very useful as the stepping stone to a 

 verymuch involved subject, and may perhaps be endorsed 

 as a whole, with the exception of what follows and the 

 consequences entailed thereby — namely the conclusion 

 at which he arrives that "vibration is the cause and 

 sound the EFFECT," in reply to which, note as follows : 



A. 1. The laws of inertia apply to aerial as well as to 

 solid bodies, only in a less degree. 



2. The vibration of air may be made apparent to the 

 ear or the eye, within the limits of their perception. 



3. These limits are not throughout coincident. 



4. The perception by eye and ear simultaneously is 

 only possible within the limits of coincident percep- 

 tions. 



Therefore to expect that what is popularly called 

 sound, viz., the perception of vibration by the ear, should 

 be concomitant with the perception by the eye, is evi- 

 dently absurd in all cases except within the limits in 

 which those perceptions coincide — otherwise vibration 

 would always be heard, when seen. 



B. 1. Air in the undisturbed enjoyment of inertia will 

 never vibrate. 



2. It may however be made to do so, by applying 

 dynamic power or energy, either muscular force, mechan- 

 ical force, electricity, heat, etc., as in the drum, siren, 

 thunder, sham-whistle, or what is popularly called the 

 " ke tie singing." 



3. The vibrating air may then be apparent to the 

 nerves of sight, hearing, or feeling. 



Therefore it is the effect of a disturbing cause, and 

 may be studied either objectively or subjectively through 

 any of those perceptions. 



We listen to the sound of the bell — what we perceive 

 by the ear is the vibration of air, the exciting cause of 

 which is the energy, which set the bell in motion. The 

 bell itself being the mechanical vibrator and resonator — 

 the loudness of the sound results from the manner 

 ot applying the energy — what musicians sometimes 

 call the "mode of attack," and do we wish to know 

 the relation existing between the energy and the vibra- 

 tion ? All that is necessary, thanks to Balfour Stewart, 

 is to use his formula, viz., that "energy is propor- 

 tional to the square of the velocity," velocity in this 

 case being as the number of vibrations per second. 

 So the vibrations of the harmonic series being related to 

 the fundamental as the whole numbers, the energy nec- 

 essary to produce this series increases in the ratio of the 

 square root of the vibrations. The resistance necessary 

 to overcome this increasing energy is peculiarly attested 

 by the lip of the cornet 1st, in the production of the 

 ascending harmonic series. 



John H.Rhodes. 



New Brunswick, November 13, 1880. 



Intensity of Certain Phenomena of Atmospheric 

 Electricity Observed in the North of the Sahara. — 

 L. Araat has observed that in tropical countries the electric 

 phenomena of the atmospheric stratum in contact with the 

 soil are more distinct than in colder climates. 



Method of Determining the Fatty Acids Contained 

 in Oils.— M. Carpentin takes a small Hat-bottomed flask or 

 a medicine phial holding about 250 c.c. Into this phial are 

 measured 50 c.c. of the sample of oil, and 100 c.c. of alco- 

 hol at go per cent., and 3 or 4 drops of tincture of tumeric 

 are added. The phial is then corked and violently shaken. 

 The phial is then placed under a Mohr's burette containing 

 a solution of 40 grms. pure sodium hydrate per litre of 

 water. As 40 grins, soda saturate 282 of oleic acid, 1 c.c. 

 of the liquid, containing 0.04 grm. soda, corresponds to 

 0.282 grm. of oleic acid. If another fatty acid has to be de- 

 termined this number is modified accordingly. The alka- 

 line liquid is carefully dropped into the phial, which is 

 shaken. When a red coloration appears it is corked, 

 agitated for a considerable time till the yellow color reap- 

 pears, the alcohol having extracted a fresh quantity of acid 

 out of oil. These operations are continued until the red 

 color becomes permanent. The number of c.c. and the 

 fraction of a c.c. consumed are then multiplied by 0.282 

 grms., in order to find the quantity of oleic acid present in 

 the sample examined. 



