Sir E. Christison. 271 



haviug given aid in conducting experiments by Dr 

 Douglas Maclagan on a new root (Hiarry) from Demerara, 

 used by the natives for intoxicating fish. And in 1838, 

 after a paper by the late Rev. Dr James Hamilton, D.D., 

 " On the Gardens of the Ancient Hebrews," Professor 

 Christison presented " Some Observations on the Preser- 

 vation of Fruits and other Botanical Specimens in the Moist 

 State." A concentrated solution of common salt made with 

 the aid of a boiling heat was recommended, and specimens 

 thus preserved for one, three, or five years w^ere exhibited. 

 At the same time dilute pyroligneous acetic acid of a den- 

 sity 1008 was shown to be most suitable for pulpy fruits. 

 This, with the well-knowm paper by Dr Greville on drying 

 plants, read subsequently, was afterwards published by the 

 Society as a separate pamphlet. In 1842 * Professor 

 Christison called attention to the Assam tea plant, then a 

 novelty of commerce, showing that different kinds of tea 

 were produced by difi'erent modes of preparation. He 

 showed by a set of examples of the preserved tea leaf, that 

 the various forms were merely varieties of the same plant. 

 The Society was also asked to inspect small rolls of tea sent 

 twenty years previously as a present from the Emperor of 

 China to King George IV. Again, in 1868, f Professor 

 Christison directed notice to the physiological effect of 

 the juice of ScopoUa htrida, Dun. (Amsodus luridns. Link), 

 in dilating the pupil of the eye to a great extent. In his 

 own eyes dilatation so produced was visible for eight days. 

 This remedy was a valuable addition to the Indian Phar- 

 macopoeia. In a communication laid before us in February 

 1871,1 Dr Christison related that somewhere between 

 1838 and 1842 he had memorialised the Board of Directors 

 for India to introduce the Cinchona culture into that 

 country. Even then the American forests of this valuable 

 tree were being wasted, w^hile the demand for the Cinchona 

 alkaloids was so steadily increasing that the tree could 

 apparently be successfully grown on great tracts of Indian 

 waste lands at a remunerative profit. Though it was 

 strongly backed by Dr Royle, the directors took no action 



* Sixth, Seventh, and Eighth Reports, p. 25. 

 + Tram. Bot. Soc. Edin., voh ix. p. 482. 

 + IMd., vol. xi. p. 110. 



