ROBIN'S GLYCERIN-GELATIN VEHICLE. 217 



CHAPTER XXL 



INJECTIONS ; GELATIN MASSES. 



431. Introduction, Injection masses are composed of a 

 coloured substance, technically termed the colouring mass, and 

 of a substance with which that is combined, technically 

 termed the vehicle. 



The following formulse are grouped according to the nature 

 of the vehicle. A note on the employment of nitrite of amyl 

 for provoking the dilatation of vessels will be found at 473. 



432. Robin's Gelatin Vehicle. (Traite, p. 30). Take some 

 gelatin, of the sort known as " colle de Paris. " (This 

 gelatin is found in commerce in the form of thin sheets, 

 marked with lozenge-shaped impressions of the cords which 

 supported them whilst drying.) Soak it in cold water, then 

 heat in water over a water-bath. One part of gelatin should 

 be taken for every 7, 8, 9, or even 10 parts of water ; it is a 

 common error to employ solutions containing too much gelatin. 

 The solution is now to be combined with one of the colouring- 

 masses given below. 



This vehicle, like all gelatin masses, is liable to be attacked 

 by mould if kept long; camphor and carbolic acid do not 

 suffice to preserve it. 



Chloral hydrate added to the mass will preserve it (HoYEE). 

 A sufficient dose, at least 2 per cent., should be employed 

 (see below, No. 445). 



433. Robin's Glycerin- Gelatin Vehicle (Traite, p. 32). Dis- 

 solve in a water-bath 50 grammes of French gelatin (" colle 



le Paris ") in 300 grammes of water in which has been dis- 

 solved some arsenious acid; add of glycerin 150 grammes, 

 and of carbolic acid a few drops. Unlike the pure gelatin 

 vehicles, this mass does keep indefinitely. 



