6 



KNOWLEDGE 



[Jan.ary, 1902. 



The castoreuiu 18 contaiiied in a couple of pouches 

 situated in the groin of the beaver, which when cx- 

 tr.icted and dried are not unlike two pears; about six 

 pouches going to tlie pound. In olden times castoreum 

 was regai'ded as an abnost universal panacea, and its 

 value wiis proportionately high. Although this sub- 

 stance no longer appears in the phamiacopoeia, in 

 America, according to the author of (hidorolngia, " the 

 belief in the miraculous properties of the castoreum is 

 still shared by so many, that the c:rude article is even now 

 regularly sold in our drug stores, and its value steadily 

 increases so that quotations of from eight to ten 

 dollars per pound are current for the rough Canadian 

 ' castors ' as the pouches are sometimes called, while 

 the Russian article is even more valuable." 



It may be added, as a somewhat remarkable circum- 

 stance, that the castoreum of the American and Old 

 World beavers differs remarkably in chemical com- 

 position, the former containing 58.6 per cent, of resin 

 and 2.6 per cent, of calcium carbonate, while in the 

 latter we find only 13.8 per cent, of the resin and as 

 much as 33.6 per cent, of the carbonate. The reason 

 for this extraordinary difference is not easy to suggest. 



Two other perfumes of animal origin, namely, 

 " musquash " and " musk-rat " are recognised in the 

 trade, but, according to information communicated by 

 Messrs. Piesse and Lubin, are at the present day of 

 no commercial value, the former being too rank, and 

 the latter too faint. It is a little difficult to trace the 

 origin of these two perfumes, since the " musquash " 

 and " musk-rat " ai'e one and the same animal — Fiber 

 ubefhicus. a North American relative of the water-vole. 

 Possibly the two kinds of perfume may be taken at 

 different seasons, or may be the product of different 

 sexes. 



Yet another substance of animal origin, held in great 

 estimation in the east, both as an antidote to poison 

 and as a remedy against all kinds of disease, may be 

 appropriately noticed in this place. This is the cele- 

 brated bezoar, which is commonly believed in Persia 

 to be obtainable only from the wild goats (Capra 

 liircus cegagrus) inhabiting the hills between Karman 

 and Shiraz, although it doubtless occurs in those of 

 other districts, and probably also in other species of 

 wild goats or ibex. The name bezoar, according to the 

 late Sir O. B. St. John, is Persian, and should properly 

 be pa-zahr, a conniption of fa-zahr, which means " use- 

 ful (for) poison." Bezoai- stones ai'e concretions 

 fonneid in the stomach of certain individuals of the 

 wild goat, and vary considerably in size, shape, and 

 colour. A specimen described in Blanford's " Zoology 

 and Geology of Eastern Persia" was egg-shaped, and 

 measured three-quarters of an inch in length ; its colour 

 being dark olive and the surface highly polished. In 

 Persia bezoars are greatly valued, and in addition to 

 being used as a medicine and as an antidote to poison, 

 are sometimes worn by the women as amulets or charms, 

 encased in gold filigree work. 



SPECTRUM OF LIGHTNING. 



Photographs of the spectrum of lightning were obtained 

 on July 18 and 21, 1901, by Mr. J. H. Freese, under 

 the direction of Mr. Edward S. King. The 8-incli 

 Draper Telescope was used with an objective prism. The 

 telescope was directed to the portion of the sky in 

 which the lightning was particularly bright, and when 

 the observer thought that he had obtained an image. 



the plate was changed. Even then many of the plates 

 wore badly fogged. A number of photographs were 

 taken in this way, and showed the curious fact that 

 tho spectrum of lightning is not always the same. One 

 flash, on July 18, showed three bright bands, while 

 another taken on the same evening showed ten bright 

 lines, and closely resembled one taken on July 21. The 

 latter is shown in Figure 1. To increase the contrast 



of the original negative a double contact print was made 

 from it with slow plates, and is reproduced in the figure 

 on the original scale. The brighter portion of a second 

 flash, cleai'ly seen in the original negative, also appears 

 m the print. Measures, each consisting of three 

 settings, were made of three poi'tions of the principal 

 spectiiim, and the means of the results are given in 

 Table I. The original negative was an isochromatic 

 plate. The successive columns give the hydrogen lines 

 with which certain of the lines are assumed to be 

 identical, the mean wave length and intensity of the 

 lines in the spectrum of lightning, and the wave length 

 and intensity of the principal lines in the spectrum of 

 Nova Persei, No. 2, on March 23, 1901. 



TABLE I. 



SPBCTBA OF LIGHTNlKa AND NOTA PEESBI. 



The first line in the spectrum of lightning is a broad, 

 bright band, extending from wave length 3830 to 3930, 

 and is perhaps identical with the nebular line 3875. 



