April 4, 1895] 



NA TURE 



541 



In the course of a few remarks made by Prof. D. E. Hughesi 

 F.R.S., at the recent banquet given by the staff of the National 

 Telephone Company, some points in connection with the early 

 history of telephony were mentioned. The text of the speech 

 is published in the EUclricai Engineer for March 22, and the 

 following note from it is interesting. Prof. Hughes said : — 

 The earliest record of a perfect theoretical electiic telephone, 

 was contained in Du Moncel's " Expos<-'e des Applications," 

 Paris, 1854 ; when M. Charles Bourseul, a French telegraphist. 

 conceived a plan of conveying sounds and speech by electricity. 

 Suppose, he explained, " that a man speaks near a movable 

 disc sufficiently flexible to lose none of the vibrations of the 

 voice, that this disc alternately makes and breaks the current 

 from a battery ; you may have at a distance another disc which 

 will simultaneously execute the same vibrations." Unfor- 

 tunately M, Bourseul did not work out his idea to a practical 

 end, but these few words contain the shortest possible explana- 

 tion of the theory of the present telephones. 



It is now exactly thirty years since Prof. Hughes first ex- 

 perimented with a working telephone. In 1865, being at St. 

 Petersburg in order to fulfil his contract with the Russian 

 Government for the establishment of his printing telegraph 

 instrument upon all their important lines, he was invited by his 

 Majesty the Emperor Alexandre II. to give a lecture before his 

 Majesty, the Empress, and Court at Czarskoi Zelo, which he 

 did ; but as he wished to present to his Majesty not only his own 

 telegraph instrument, but all the latest novelties. Prof. Philipp 

 Reis, of Ftiedericksdorf, Frankfort-on- Maine, sent to Russia 

 his new telephone, with which Prof. Hughes was enabled to 

 transmit and receive perfectly all musical sounds, and also a 

 few spoken words, though these were rather uncertain, for at 

 moments a word could be clearly heard, and then from some 

 unexplained cause no words were possible. This wonderful 

 instrument was based upon the true theory of telephony, and it 

 contained all the necessary organs to make it a practicable suc- 

 cess, lis unfortunate inventor died in 1874, almost unknown, 

 poor, and neglected ; but the German Government have since 

 tried to make reparation by acknowledging his claims .as the 

 first inventor, and erecting a monument to his memory in the 

 cemetery at Friedericksdorf. 



Since the enunciation by Virchow, in 1858, of his theory 

 of cellular pathology, much attention has been given to 

 the study of this unit. Nearly all the unsolved prob- 

 lems of medical science involve, in one way or another, the 

 consideration of some one of the functions of the cell. At 

 the Philadelphia Academy of Natural Sciences, on February 5, 

 Dr. C. L. Leonard directed attention to a new method of 

 studying one of these functions. The method consists in 

 making a consecutive series of instantaneous photomicro- 

 graphs of the same microscopic field, taken at definite 

 intervals, so that a comparative study of the series can 

 afterwards be made. The results obtained by this method are 

 the elimination to a greater extent of the personal equation of 

 the observer, the procuring of incontestable proof of phenomena 

 observed, the extension of the observations over any length of 

 time, and the possibility of studying the changes occurring over 

 the entire field at any one moment. The method also enables 

 the student to study the condition of a fresh, living, unstained 

 specimen for any length of time, in fields taken at definite 

 atervals. So far Dr. Leonard has confined the greater part of 

 his study to cell motion as exemplified in the movements of the 

 red and white blood corpuscles. He exhibited to the Academy 

 a number of photomicrographs illustrating the amccboid motion 

 of the white blood corpuscle, and also showing motion in the red 

 blood corpuscle. Some of the photographs seem to show that 



NO. 1327, VOL. 51] 



diapedesis is not a filtration due to pressure, but is due to a 

 truly amoeboid motion and power of the red blood corpuscles. 

 Further photographs illustrated the position of the corpuscles 

 within the capillaries, and showed the presence of nuclei in the 

 red corpuscles of the frog while in the living tissues. 



At a recent meeting of the Paris Academy, M. Desire 

 Korda read a paper on a " thermochemical carbon 

 cell." The author finds that if barium peroxide is 

 heated to redness in contact with a carbon plate, the 

 oxide becomes reduced to baryta, and a difference of poten- 

 tial of about one volt is produced, the carbon plate being 

 negative. A similar result was obtained with cupric oxide as 

 soon as a layer of potassium carbonate was placed between the 

 oxide and the carbon, the difference of potential in this case 

 amounting to II volts. The experiments were in each case 

 performed by connecting a plate of gas-retort carbon by means 

 of a platinum wire to one terminal of a Richard voltmeter, and 

 placing on the carbon a few c.c. of the salt. A platinum wire 

 dipping in the salt served to complete the circuit. On heating 

 the carbon to a dull red heat in a Bunsen flame, a violent 

 effe rvescence takes place, carbon dioxide being evolved, and 

 the voltmeter shows a deflection corresponding to about I volt. 

 T his deflection remains constant as long as any of the higher 

 oxide is left. 



Readers of Mr. Edward Step's books and magazine articles 

 on popular botanical subjects, will be pleased to learn that he 

 has writ ten a pocket-guide to British wild flowers, to be pub- 

 lished by Messrs. Frederick Warne and Co. The title of the 

 book will be "Wayside and Woodland Blossoms." 



The fourth part of " Dissections Illustrated " (Whittaker 

 and Co.;, by Mr. C. Gordon Brodie, containing sixteen mag- 

 nifi cent plates drawn and lithographed by Mr. Percy Highley, 

 has just appeared. Students of human anatomy could hardly 

 des ire a handbook in which typical dissections are more clearly 

 displayed than they are in Mr. Brodie's work, which has now 

 been completed. The whole work contains seventy-three 

 coloured plates.-diawn to two-thirds natural size. 



The Zoological Society of France has just published a new 

 edition of the " Rules of Nomenclature of Organised Beings 

 adopted by the International Congresses of /oology (Paris, 

 1889 ; Moscow, 1892)." A copy will be sent gratis to every 

 professor of zoology or comparative anatomy, director of a 

 museum, library or laboratory, or assistant in the same, also to 

 every learned society, upon application to the general secretary, 

 M. le Dr. R. Blanchard, 7 Kue des Grands Augustins, 

 Paris. 



The valuable work in zoology, carried on in H.M. Indian 

 Marine surveying steamer Investigator, under Commanders 

 A. Carpenter and R. F. Hoskyn, is already known to many 

 biologists, ar.d Part I. of the illustrations referring to it, 

 now obtainable through Mr. Bernard Quaritch, should make 

 it known to more. The Part contains seven splendid photo- 

 etchings representing twenty-six remarkable fishes, and five 

 illustrative of Crustacea. The former were prepared under the 

 direction of Mr. A. Alcock, and the latter under the direction 

 of Mr. J. Wood-Mason. 



Prof. S. H. Vines' "Students' Text-book of Botany" 

 (Swan Sonnenschein and Co.), the first half of which was 

 reviewed in these columns in October last (vol. 1. p. 613), has 

 just been published in its complete form. In addition to the 

 sections mentioned in our notice, the work now contains 

 descriptions of the Phanerogams, and the part on the physiology 



