XXIXJ DRUGS 361 



Treat 1 gram of the whole or powdered sample in a 700 cc. round-bottomed, long- 

 necked flask for several hours in the cold with 100 cc. of water and 5 cc. of sirupy 

 phosphoric acid until the gum is completely swollen. Boil gentlj' for 2 hours under 

 a reflux condenser. A very small amount of cellulose substance will remain undis- 

 solved. Now distil the hydrolyzed product with steam, using a spray trap' to con- 

 nect the distillation flask with the condenser and continue until the distillate 

 amounts to 600 cc. and the acid residue to about 20 cc. Do not concentrate too far, 

 as this would scorch the non-volatile, organic decomposition products and possibly 

 contaminate the distillate. Titrate the distillate with N/10 potassium hydroxid, 

 using 10 drops of phenolphthalein as an indicator, finally boiling the liquid under 

 examination until a faint pink color remains. Correct the result by a blank de- 

 termination and express the final result in terms of the number of cc. of N/10 

 alkali required, as in the above definition. 



While tragacanth yields a practically colorless solution when boiled with aqueous 

 phosphoric acid, Indian gum, on the other hand, gives a pink or rose solution. This 

 reaction may be used as a preliminary test for the detection of Indian gum. 



Levant Wormseed. 



32 santonin.— tentative. 



Extract 10 grams of the sample, ground to pass a 30 mesh sieve, in a Soxhlet ex- 

 traction apparatus for 3 hours with chloroform. Distil oflf the chloroform until 

 7-8 cc. remain; add 100 cc. of 5% barium hydro.xid solution and heat on a steam 

 bath until the odor of chloroform has disappeared. Boil 5 minutes, cool and pass 

 carbon dioxid (washed through sodium bicarbonate solution to remove traces 

 of acid) until saturated. Filter on a small Biichner funnel, using suction, and wash 

 twice with 10 cc. of water. Heat the filtrate on a steam bath, add 5 cc. of 25% 

 hydrochloric acid and warm 5 minutes. Cool until lukewarm and extract with 20, 

 15 and 15 cc. of chloroform, passing the solvent through a small filter into a flask. 

 Evaporate to dryness, removing the last traces of chloroform. Dissolve in 7.5 

 grams (9.5 cc.) of absolute alcohol, warming gently if necessary. Then add 42.5 

 cc. of water heated to 60°-70°C., stopper the flask and allow to cool. Start crystal- 

 lization at this point by scratching the side of the flask with a rod or by seeding with 

 a minute crystal of santonin. (Solutions containing a liberal amount of santonin, 

 kept in a cool place for 24 hours, have been found in a supersaturated condition 

 where this precaution was not observed.) Maintain the flask and contents at a 

 temperature of 15°-17°C. for 24 hours. Filter and wash at 15''-17°C. with two 10 

 cc. portions of 15% alcohol by weight. Dry the flask and filter at 100°C., dis- 

 solve the santonin left in the flask and on the filter in chloroform and filter into a 

 tared beaker. Wash the flask and paper thoroughly with chloroform, evaporate 

 the combined filtrate and washings, dry at 100°C. to remove all traces of chloroform 

 and weigh. To the weight found add 0.04 gram for the santonin dissolved in the 

 dilute alcohol and multiplj' the total by 10 to obtain the per cent of santonin. 



Nitroglycerin in Tablets. 



33 preparation of sample.-tentative. 



(a) Crush 25 tablets under 10 cc. of anhydrous ether in a 25 cc. cylinder by 

 means of a stout glass rod. Rinse the rod with a little anhydrous ether, allow 

 the insoluble material ^o settle and decant the solution into a 50 cc. jjraduated 

 flask. Wash the residue repeatedly with 5 cc. portions of anhydrous ether, decant 

 the washings into the flask until it is filled to the mark, stopper and mix well. 

 Designate this solution as .1. 



