SCIENCE. 



47 



Experience has shown that with such a lamp it is possible 

 to obtain, with regularity and safety, a good electric light 

 with twenty-four Bunsen cells, and at first with even twenty 

 cells. Some of these lamps have been in use in the Rus- 

 sian artillery since 1877. Ihis lamp may also be constructed 

 on the principle of the Wheatstone balance. 



The form of my lamp intended for public lighting is 

 represented by Fig. 2. The rod A, with the upper carbon- 

 holder works by the effect of its own weight. When the 

 current traverses the lamp the distance between the two 

 carbons is maintained by the aid of helical coils, but these 

 coils and the toothed wheel which controls the movements 

 are worked, as in the former case, on the principal of deri- 

 vati ons. When the current is interrupted, the carbons come 

 into contact by the effect of the weight of the rod A. 



I omit here certain details of construction which are of 

 importance in order that the lamp may work properly. 



To sum up, the advantages of my lamp may be enumera- 

 ted as follows : 



1. Its construction is extremely simple, it is free from 

 clockwork mechanism, springs and electrical contacts. 



2. It does not require preliminary regulation nor any 

 manipulation before or during its working. 



3. Several of these lamps may be arranged in series in 

 a circuit, and they are always in due relation with the inten- 

 sity and the tension of the current which is to act upon 

 them. 



4. The lamp can work with comparatively weak currents, 

 and also produce a very powerful light when the power of 

 the current is augmented. 



I am convinced that the problem of the divisibility of the 

 electric light by means of lamps having a voltaic arc can be 

 solved only with the lamps based on the principle of the 

 derivation of the current, which I discovered prior to 

 Messrs. Lontin and Siemens. 



Lamps with movable carbons offering a certain resistance 

 between their polar extremities are moreover far preferable, 

 from the point of view of divisibility, to lamps with fixed 

 carbons (with carbons at a fixed distance ?) which may offer 

 great variations in the resistance of the arc, in consequence 

 of impurities, the action of the wind, &c. These variations 

 may in fact be greatly reduced in the former description of 

 lamp, and it is not necessary with them to employ currents 

 of such high tension or, if such currents be employed, ad- 

 ditional lamps may be inserted in the circuit. 



W. TCHIKOLEFF. 



GENERAL NOTES. 



Climatic influences have of late been rather against 

 phylloxera, which has shown, therefore, a decreased activity 

 lor a time. According to M. Boiteau, the treatment with 

 sulphide of carbon and sulphocarbonate of potassium 

 these past three years past seems to have had even a stimulat- 

 ing effect on the vines (besides ridding them of the insect). 

 Some of the vines thus treated are flourishing better than 

 before the parasite appeared. 



M. Charnay, the leader of the expedition recently sent 

 to Central America under the auspices of the governments 

 of the United States and France, the expenses of which are 

 to be largely borne by Mr. Pierre Lorillard, telegraphs that 

 the Mexican government has signed a treaty giving him all 

 the privileges and facilities he needs in making explorations 

 and has appointed a representative to accompany him. 



Marie Ekunina describes, in the Journal fur Praktische 

 Chemie, an investigation conducted in Professor Nencke's 

 laboratory at Berne, on the causes of acid reaction of the 

 animal tissues after death. This reaction is attributed to 

 the decomposition of tissue juices, after death, by fungi. 

 Volatile fatty acids first arise through commencing decom- 

 position of albumin, but very soon the two lactic acids 

 proceeding from glycogen are associated with these. The 

 richer the tissue in carbohydrates, the longer does the acid 

 reaction continue after death ; this is especially the case 

 with liver, muscles, and lungs. The shortest and weakest 

 acid reaction is that in the pancreas. Sooner or later, in 

 all tissues, the acid reaction passes over into an alkaline, 

 while the decomposition of albumin increases, and there 

 is much formation of ammonia. 



CORRESPONDENCE. 



We have been requested by a correspondent of Lieu- 

 tenant Colonel Ross to publish the annexed letter, which 

 at present may be accepted as an ex-paite statement, which 

 complains of a wrong done to him by certain members of 

 the Royal Society. But while placing our columns at the 

 disposal of Col. Ross, we disclaim any personal responsi- 

 bility in the matter, and will afford ample space for any 

 reply which Professor H. E. Roscoe, or others concerned, 

 may decide to forward to us for publication. Lt. Col. Ross 

 is well known for his works on Blow-pipe Analysis, and 

 has recently published a small manual on this subject, 

 which we find favorably spoken of by the English Scientific 

 press. — [Ed.] 



London, nth June, 1880. 



To the Secretary of the Royal Society. 



Sir. — In forwarding a copy of my new work on the Blow- 

 pipe, for the Library of the Royal Society (which I did yes- 

 terday), I have the honor and pleasure to inform you for 

 communication to them, that I have now, beyond reason- 

 able doubt, discovered the coloring principle of the Sap- 

 phire, and can produce stones made chiefly of alumina, of 

 almost any required tint of blue, green, or " amethyst," 

 without using any chromatic oxide -whatever, a discovery I be- 

 lieve to be quite unique, for, although a Belgian or 

 French chemist has made real "rubies," he is obliged to 

 color them with manganese or other metallic oxide. 1 do 

 not propose, however, to communicate this secret to the 

 Royal Society, as I at first intended, for the following 

 reason : When in the Spring of 1873, the Secretary of your 

 Society, with the discriminating perception of the useful 

 and novel which is characteristic of men of genius, came 

 to Woolwich to examine experiments which I was then 

 (as a Captain in the Royal Artillery) making in blow-pipe 

 analysis, and eventually read a paper on the subject before 

 your Society, I little thought that influential opposition in- 

 stituted by Fellows of your Society, would be the chief 

 cause of retarding my humble efforts in the progress of this 

 new science for nearly ten years. I have, however, the 

 most reliable evidence to prove that Professor H. E. Roscoe, 

 F. R. S., and another Fellow of your Society whom I need 

 not mention here, circulated the most disparaging and de- 

 preciatory opinions regarding the novel statements on this 

 subject contained in my work " Pyrology," (a detailed ex- 

 position of the views first propounded in the paper read 

 before your Society,) the MS. of which was offered by me 

 to Messrs. Macmillan & Co., in 1874, for publication and 

 declined by them, presumably on the advice of Prof. Roscoe. 



Of course I have no right, nor do I for a moment wish to 

 complain of the adverse opinion of eminent men of science, 

 though perhaps such opinions would be more suitably ex- 

 pressed in public so as to give me an opportunity of reply ; 

 but what I venture most respectfully now to complain of, is 

 that one of my inventions in Blowpipe Analysis — the use of 

 Aluminium plate — which had been disparaged as above 

 mentioned, has now been adopted by that department of 

 Owens College, Manchester, over which Prof. Roscoe so 

 eminently and justly presides, and that a German work on 

 the subject, translated in that department, has interpolated 

 in it an account, spread over thirteen pages, of the very 

 Aluminium plate reactions rejected by Prof. Roscoe in 

 1874, and, worst of all, the invention is attributed to some- 

 body else in the index of the book, which has been adopted 

 as a text book by the Owens College. 



As I have sustained a serious loss by the publication of 

 my work on the subject, chiefly through the opposition 

 above referred to, I would most respectfully ask the council 

 of your society whether they do not think it fair that I 

 should reap any benefits now, derivable from my inventions 

 or discoveries ? I have the honor to be, Sir, 



Your most Obedient Servant, 



W. A. Ross, Lt. Colonel, 

 Royal Artillery (retired list). 

 The Secretary Royal Society, 



Burlington House, Piccadilly W. 



