BY J. M. PETRIE. 127 



(f ) The solution was diluted to 1 part of residue in 500 normal 

 saline (1 in 1000 alkaloid), and when one drop of this was in- 

 stilled into the eye of a dog, wide dilatation was produced in 

 about 20 minutes. The alkaloid was therefore of the midriatic 

 group. 



Evidence was thus obtained from these results that the 

 alkaloids assumed to be non-volatile, had distilled over in small 

 quantities, under the conditions stated. The next step, there- 

 fore, was to ascertain the behaviour of pure atropine, when 

 treated in the same way. 



xvi. Control experiment. — Method: — Pure atropine sulphate 

 solutions with excess of lime, with and without sawdust, were 

 distilled in a current of steam, from a flask fitted with a Kjeldahl 

 spray-trap. At the end of each hour, the distillate which 

 reacted alkaline to litmus, was shaken out with chloroform. 

 The chloroform extract was then washed and dried, and the 

 solvent distilled off. The residues were weighed and titrated, 

 and afterwards examined. 



Results: — Very erratic results were obtained. Tn some, the 

 amount of residue decreased to nothing in the five successive 

 hours. In others, they varied much, even increasing at the end. 

 In general, a total weight of 20mgs. was obtained after five 

 hours. This yield was apparently independent of the amount of 

 alkaloid taken, which was between 0-1 and 1 -Omg. The addition 

 of sawdust did not alter the result. All the residues contained 

 alkaloid. 



When a distillate, without previous neutralisation, was 

 evaporated in an open basin over a bunsen flame, the residue 

 contained only a trace of alkaloid. 



(a) By titration of these residues as in the previous series, 

 the amount of alkaloid (as atropine) in five hours' distillation 

 was 1 1 mgs. If the latter be taken as representing the actual 

 amount of alkaloid in each total distillate, then the alkaloid has 

 distilled over under the conditions of these experiments at a 

 rate of 2 mgs. per hour. From these titrated solutions, the 

 alkaloid was recovered and examined. 



