82 



Messrs. Jones and Dupre on a Substance^ [Apr. 12, 



Secondly. On the increase of fluorescence that was observed when dif- 

 ferent quantities of sulphate of quinine were given to animals at diiferent 

 periods before they were killed : — 



9. A guineapig was given sixteen grains of sulphate of quinine, in nine 

 doses, in the course of four days. It was found dead more than twelve 

 hours after the last dose. Its fluorescence was compared with pig 2, 

 which had taken no quinine ; the lenses and the nerves, treated the same 

 way, showed much more fluorescence in the pig that had taken quinine 

 than in the other which had had no quinine. The solutions of the lenses 

 and the nerves also gave a distinct precipitate, which was least in the solu- 

 tion of the lenses with solutions of iodine and of iodide of mercury ; whilst 

 the solutions of the lenses and the nerves of the pig that had taken no 

 quinine remained clear. The bile and the brain fluoresced brightly. The 

 solution of the liver, when diluted even to one hundred minims, fluoresced 

 distinctly in daylight, and very strongly in the light of the spark. The 

 brain-solution gave a distinct precipitate with iodine and iodide of mercury. 

 The bile gave a very faint turbidity. The liver gave an abundant preci- 

 pitate, and moreover gave Herapath's test for quinine very distinctly. 



10. Another pig took twenty-six grains of quinine, in fourteen doses, 

 during six days. It was killed nineteen hours after the last dose, being ap- 

 parently partially paralyzed. The solutions of the diiferent organs were 

 prepared in the same way as 9 and 2, and they were examined at the same 

 time. The lenses showed the fluorescence very strongly when a cone of 

 sunlight was thrown into them with a quartz lens. The humours showed no 

 fluorescence at all in this manner. The solutions of the bile, brain, urine, 

 nerves, lenses, spinal marrow, liver, gave more or less distinct fluores- 

 cence. The solution of the brain gave no precipitate with iodine or 

 iodide of mercury ; nor did the bile give a precipitate, but the liver gave 

 a slight precipitate with both reagents. 



Ha^dng thus satisfied ourselves that quinine does pass into the vascular 

 and non- vascular tissues, we proceeded to determine how quickly four, five, 

 or six grains of sulphate of quinine given to guineapigs could be detected 

 in the difl'erent textures of their bodies. 



11 . A guineapig was given four grains of sulphate of quinine, and it was 

 killed in one quarter of an hour ; all the extracts from the difl'erent parts 

 of the body were mixed with one-eighth of their bulk of dilute sulphuric 

 acid, and were made up to twenty-five minims. The amount of fluorescence 

 was compared with the fluorescence obtained in pig 6, and with standard 

 solutions of sulphate of quinine with one-eighth of dilute sulphuric acid, 

 containing one grain, three-quarters, half, one-eighth, one-sixteenth, and 

 one-thirty-second of a grain of sulphate of quinine. The solutions of the 

 extracts of pigs 19, 22, 25, and 26, which had taken four grains of sulphate 

 of quinine and were killed six hours, twenty-four hours, forty-eight hours, 

 and seventy-two hours after the quinine was taken, were examined at the 

 same time. 



