106 APPENDIX. 



sulphuric acid. Witli this aim in view, 50 gi-ams of finely powdered 

 opium were rubbed together with distilled water and the paste 

 washed completely into a dialyser consisting of an oval gutta-percha 

 ring covered with heavy parchment paper and immersed in a dish 

 containing about five litres of distilled water. This was allowed to 

 stand covered thus for nearly three months, the water being changed 

 about twice a week. Even at the expiration of this time, sulphuric 

 acid and alkaloids could be detected in the dialysate, and as my time 

 here was limited, and the semester was rapidly drawing to a close, 

 it was decided to finish the operation more expeditiously by 

 exhausting the opium remaining in the dialyser with cold water. This 

 last extract was treated separately, although exactly in the same 

 way as the greater portion. While this operation was quietly pro- 

 gressing, a complete analysis of the ash of opium (tlie same as was 

 used for dialysis) was made in order thus to get a definite idea of 

 the mineral constituents of the drug. Accordingly, 20 grams of 

 finely powdered opium were carefully and gradually ignited in por- 

 tions in a platinum dish. It was found very difficult to completely 

 incinerate the drug, so that even after heating the dish to a bright 

 red heat the resulting ash was quite dark, in fact nearly black. It 

 was found very advantageous at this point to treat the mass with a 

 little cold water ani evaporate this off on a water-bath, and finally, 

 again carefully heat and glow it over a free flame. By repeating 

 this operation several times, an ash was obtained, which was veiy 

 nearly pure white in colour. When weighed, it yielded 3-89 

 per cent, of the original substance. 



A complete analysis, the details of which it would be useless to 

 enumerate here, gave the following results, these being expressed 

 in per cent, of the ash weighed : 



SiO» 



P205 



CaO 

 MtrO 



*** •«■ ««• ••• 



•*• '•' ••♦ »•» trt 



Per cent, 

 IM4 



•• »»t *vt 



■ fl • 



• f 9 t « « 



• ■ • ■ • • ■•! 



8-07 



— '•• .'. ... 28-3^ 







C5 • '• t*9 . rv 



K^O 



•" •*• , ».» 



1-9S 

 9-04 

 8"3l 



••' ••• ♦»• ... .r. 



30'19' 

 C0«,HC1 and unjetermined constituents '/ '" 2-83 



lOO-O^ 



