Observations and Experiments on Opium. 29 



From either of the above combinations morphia may be 

 separated by ammonia. 



The acetate of morphia is the most active preparation, 

 and as it is a very deliquescent salt, it is extremely difficult to 

 obtain it in crystals. Under these circumstances, the follow- 

 ing process has been recommended to make the acetate from 

 the morphia. 



Take morphia 4 parts, distilled water 8 parts, dilute the 

 morphia in a porcelain vessel, afterwards add acetic acid 

 sp. gr. 1.075, (pure concentrated pyroligneous acid,) until 

 turnsol paper becomes scarcely red by its action ; evaporate 

 the solution to the consistence of syrup, continue the evapo- 

 ration slowly either in the sun or in a stove, collect the salt 

 and reduce it to powder.* 



The sulphate is the next most active salt of morphia, and 

 is employed where patients have been accustomed to the use 

 of the acetate, for generally by varying the salts of alkaline 

 medicines, their action may be kept up longer without in- 

 creasing the dose too considerably. Formulas for the pre- 

 paration of these salts in syrups, mixtures, solutions, &c. 

 are given in Haydens, Formulary and Formulaire de Mont- 

 peJlier. 



The other salts of morphia, with the exception of the citrate, 

 tartrate and meconite have not yet been employed in me- 

 dicine. 



Meconic Acid, 



Exists in combination with morphia, in crude opium, form- 

 ing a meconite of Morphia ; it is to this salt that laudanum 

 owes its narcotic effects. Our distinguished chemist Dr. 

 Hare, has in the preceding number of this Journal, given an 

 easy process for obtaining this acid; the same gentleman has 

 also given in the same number of the Journal, a very deli- 

 cate test and an easy mode of detecting minute quantities of 

 opium in solution. It consists in precipitating the meconic 

 acid with acetate of lead ; the meconic acid is liberated from 

 the lead by sulphuretted hydrogen or sulphuric acid, to which 

 add a solution of the sulphate of iron which produces a 

 striking red colour. Professor Hare observes, that a quantity 

 of opium not exceeding ten drops of laudanum may be detec- 

 ted in a half gallon of water ; his observations on the sub- 



* Pharmacopeia Gallica, 1818, page 387. 



