314 ANNUAL OF SCIENTIFIC DISCOVEEY. 



THE ORDEAL BEAN OF CALABAR. 



At a recent scientific meeting in London, Prof. Harley exhibited 

 specimens of the bean employed by the King of Calabar as a poisonous 

 ordeal to determine the guilt or innocence of accused persons. The 

 plant yielding this bean is kept secret from the natives generally, and 

 the seeds are consequently to be obtained only with great difficulty. 

 The name that has been given to the plant is Plnjsostigma venenosum, 

 or Calabar ordeal bean. It belongs to- the leguminous tribe, having 

 distinct papilionaceous flowers succeeded by pods six inches in length, 

 each containing four or five seeds, having white cotyledons, resembling 

 in taste the seeds of the common haricot, Phaseolus vulgaris. Taken 

 internally, the beans, unless rejected by vomiting, produce fatal paral- 

 ysis. In some experiments made in this country it has been found 

 that twelve grains have produced^ partial paralysis, threatening to be 

 serious in its results. In the course of investigation into its properties, 

 it has been ascertained that the extract of the bean possesses a most 

 extraordinary power over the iris, a few minims of its solution dropped 

 into the eye causing contraction of the pupil to such an extent that the 

 aperture becomes entirely obliterated, and the eye possesses the ap- 

 pearance of having an imperforate iris. In order to demonstrate this 

 action more fully, and to contrast it with the opposite effect of a solu- 

 tion of belladonna, a cat was exhibited, to one eye of which belladonna 

 had been applied several days previously, causing dilatatio of the pu- 

 pil to such an extent that the iris was scarcely visible ; to the other 

 eye a solution of the ordeal bean had been applied, which caused ob- 

 literation of the pupil. The contrast between the two eyes of the ani- 

 mal was of the most marked character, and imparted a strange weird 

 expression to the face. In the course of the evening the pupil dilated 

 somewhat the effect of the Physostigma passing away gradually in 

 the course of about twenty-four hours, whereas that of the belladonna 

 persists for many days. Specimens of the plant have been raised in 

 England from the imported seeds. 



OZONE EXHALED BY PLANTS. 



In an elaborate memoir presented to the Academy of Sciences, at 

 Paris, M. Kosmann gives an account of a series of experiments in re- 

 gard to this subject, carried on at his own house in the middle of Stras- 

 burg, in the Botanic Garden of that city, and in a spacious garden 

 above thirty miles from it : these three places seeming to offer the dif- 

 ferences which should characterize vegetation in the midst of towns 

 and that of the country in various degrees. He made use of Schb'n- 

 bein's ozonometric scale and ozonoscopic bands, fixed on the plants. 

 For details we must refer to the Comptes Rendus. He gives the fol- 

 lowing as the results of his observations from July 29 to Sept. 14 last. 

 (He proposes to resume his studies in the spring.) "1. Plants give off 

 ozonized oxygen from the midst of their leaves and green parts. 2. 

 Their leaves give off during the day ozonized oxygen in ponderable 

 quantity, much greater than that which exists in the surrounding air. 

 3. During the night this difference disappears where vegetables are 

 sown sparingly ; but where there is an accumulation of plants, and 

 they grow vigorously, even in the night the ozone observed in the 



