May 13, 1 897 J 



NATURE 



39 



bourhootl of Melbourne ; and the values of the wave-lengths of 

 the spectrum lines of the alkalies, as determined by a new 

 periodic formula. — A discourse pronounced by the late Dr. 

 du Bois-Reymond in honour of the memory of Hermann von 

 Helmholtz, is now published by \'eit and Co.. Leipzig. The 

 'liscourse is a full and valuable statement of lielmholtz's life 

 .nd scientific work. 



The additions to the Zoological Society's Gardens during the 

 past week include an Orang-outang {Siinia satyrus, 9 ) from 

 Borneo, presented by Lord Ashburton and the Earl of Crawford ; 

 a White-crowned Mangabey [Cercscebns ccthiops^ 9 ) from West 

 Africa, presented by Mr. Bernard A, Collins ; a Malayan Bear 

 < Ursus maiayanus, 9 ) from Malacca, presented by Lord and 

 Lady Ashburton ; a Nightingale {Daulias Itisctiiia), British, 

 presented by Mr. W. IL St. <^)uintin ; three Common Boas 

 {Boa constrictor) from the Tefile River, Upper Amazons ; a 

 Brazilian Tortoise (Testiido tabnlata) from Brazil, presented by 

 Mr. H. C. FeTnando Rohe ; a Phayre's Tortoise ( Testiido einys) 

 from Borneo, presented by H.H. the Tuan Muda of Sarawak ; 

 a Forsten's Lorikeet {Trichoglossus Jorsteni) from Sumbawa, a 

 Blue-faced Lorikeet (Tric/ioglossus Jiu-matodes), two Perfect 

 Lorikeets (Psittetttelcs entelcs) from Timor, a Phayre's Tortoise 

 {Testiido einys) from Borneo, deposited ; a Malbronck Monkey 

 {Cercopithecus cynositrits, i) from Congoland, two Phayre's 

 Tortoises ( Testudo eniys) from Borneo, two Long-tailed Grass- 

 Finches [Poepfiila acuticanda) from North-west Australia, 

 i urchased. 



OUR ASTRONOMICAL COLUMN. 



May Meteors.— During the month of May the number of 

 meteors is by no means considerable, the records showing quite 

 a dearth of deduced radiant points at this season of the year. 

 One, however, which seems to be, to some extent, prominent 

 {Asir. Nach., No. 3418), is that which is situated in the region 

 near the brightest star in Corona. The Greenwich observers in 

 1866 one evening recorded no less than seven first magnitude 

 meteors, and five fainter ones, in the course of an hour ; and Mr. 

 Denning tells us that he himself made some very successful 

 observations in 1885. This observer is of opinion that previous 

 observations indicate the occurrence of a special shower, and 

 he gives, as a mean of many determinations of the positions of 

 radiant points, the coordinates 232° "8 -f- 28° '6. May i8isgiven 

 :is the day on which special attention should be devoted to this 

 'ihower. 



Centralsteile Telegrams.— We have received a com- 

 munication from Prof. H. Kreutz, in Kiel, which informs us 

 that he has taken over definitely the direction of the Central 

 Bureau for astronomical telegrams, and that in future the tele- 

 graphic address will not be Bureau der Centralsteile, Koniglichen 

 •Sternwarte, Kiel, but Astronomische Centralsteile, Kiel. Prof. 

 Kreutz also incloses the " Statutes " of the Centralsteile, which 

 have been recently revised. 



Accidental Errors of Talcott Observations. — From 



a series of observations, 500 in number, made with the object of 



-letermining the latitude of Hong Kong, Herrn Doberck {Astr. 



Xach., No. 3418) states some interesting facts about the choice 



. cgarding magnitude of stars that will be useful to observers using 



I he Talcott method. It has been previously found that neither 



the zenith distance, nor the amount of the difference of zenith 



distance, if within 10', affects the error of the results ; neither 



is the difference of right ascension, if less than 20 ni., affected. 



I lerrn Do1)erck suggests that these limits might with advantage 



»i extended : it is better to "observe bright stars with zenith 



iistance greater than 20", difference of right ascension greater 



iian 20 m., and difference of zenith distance greater than 10', 



!ian to observe fainter stars within these limits, as the accidental 



errors of observation increase when the brightness of the stars 



<lecreases." Taking the average magnitude of each pair of stars 



from 3*5 magnitudes up to the 7th magnitude, he gives a table 



showing the probable errors of one observation for each increase 



of half a magnitude. 



NO. 1437, VOL. 56] 



FURTHER STUDIES ON SNAKE POISON AND 



IMMUNITY. 

 "P R(JF. CALMETTE, whose name is so indissolubly associated 

 with the study of snake bites and their treatment by anti- 

 venomous serum, has lately published in the Pasteur Ann-ales, in 

 conjunction with his assistant ^L Delarde, a most interesting 

 and highly important series of experiments helping to elucidate 

 the mechanism of immunity. Endeavouring to throw light upon 

 some of the problems surrounding this highly complex question, 

 Calmette has selected two different kinds of toxin, the one 

 vegetable and the other animal. 



The vegetable toxin was furnished by the substance known as 

 abrine, which is the active principle of the seeds or beans of 

 ahrits precatoriiis, a leguminosa conjmon in India and South 

 America. It is a highly toxic material, and one milli- 

 gramme suffices to kill a rabbit in forty-eight hours. Very 

 few animals apparently can resist its action, and so far as 

 Calmette's observations go, this immunity is restricted to hedge- 

 hogs, fowls, tortoises, snakes (coiileiivres) and frogs. It requires 

 as much as ten milligrammes of abrine to destroy either a hedge- 

 hog or a fowl in forty-eight hours, whilst a tortoise only 

 succumbs after a dose of thirty milligrammes. 



The animal to.vin selected for these experiments was, as might 

 be expected, serpent venom, consisting of a mixture of venoms 

 derived from various kinds of poisonous snakes. 



In the course of his previous researches, Dr. Calmette was 

 led to believe that snakes had a charmed life against all in- 

 jections of serpent venom ; but he now tells us that his earlier 

 conclusion requires correction. He has succeeded in killing 

 Egyptian asps and a serpent native to Indo-China by injecting 

 doses of venom three limes as great as that normally present in 

 their respective poison glands, and he is, therefore, of opinion 

 that although reptiles do possess great powers of resisting the 

 toxic effect of serpent venoms, yet, contrary to what he at first 

 supposed, their immunity to this poison is not absolute. 



Various hypotheses have been suggested to account for this 

 comparative immunity exhibited by reptiles to the effect of 

 venom, and Prof. Eraser, of Edinburgh, has attributed this 

 phenomenon to the presence in the blood of reptiles of some 

 anti-toxic substance. Calmette, however, has shown that, far 

 from protecting animals from the toxicity of venom, reptile 

 blood causes their death. Experiments in this direction were 

 not only made with the blood derived from the liver and other 

 organs of a iiaja tripiidians, but also with injections of a filtered 

 aqueous emulsion of these organs, but in no case was any pro- 

 tective action recorded. 



Again, the serum of pigs, which animals in some countries 

 are specially trained for the purpose of hunting serpents, which 

 they devour greedily without suffering the least inconvenience 

 from their biles, the serum of these animals has no modifying 

 action whatever outside the body, in vitro, on serpent venom, 

 and has no protective action. 



Similar experiments were also made with animals exhibiting 

 a relative immunity to the toxic action of the vegetable ]ioison, 

 i.e. abrine. It was found that whereas the normal serum of 

 hedgehogs, which animals possess a natural immunity to abrine 

 poisoning, can protect other animals susceptible to this toxin 

 from its lethal effects, yet to do so effectually large quantities of 

 the serum in question must be employed. On the other hand, 

 fowls and tortoises*, although also naturally immune to the 

 abrine toxin, can confer, by means of their serum, no protective 

 power whatever upon other animals against this poison. 



The next question approached by Calmette was whether these 

 so-called refractory animals can elaborate antitoxins, and in the 

 course of his experiments on this subject he obtained some very 

 curious results. 



For these investigations abrine only was employed, and pro- 

 fiting by the fact that fowls and tortoises had proved very 

 refractory to this toxin, these animals were chosen as subjects for 

 the inquiry. 



Two fowls were given, in the course of twelve days, about 

 eight milligrammes of abrine. Whilst, as we have seen, ordinary 

 fowl-serum can confer no immunity from the effects of abrine 

 poison, the serum derived from the abrine-treated fowl was pos- 

 sessed of immunising properties. In this case, therefore, a 

 refractor)- animal, normally incapable of yielding an anti-toxic 

 serum, had been trained by artificial means to do so. Similar 

 experiments made with another refractory animal gave, how- 

 ever, quite different results, for when tortoises were treated with 

 abrine poison, instead of their serum acquiring any protective 



