74 PHILOSOPHICAL TRANSACTIONS. |_ANNO 1750. 



Tartarus solubilis 2 Salt of hartshorn 4+ 



Sal diureticus 2+ Salt of wormwood 4 + 



Crude sal ammoniac. 3 Borax 12+ 



Saline mixture 3 Salt of amber 20+ 



Nitre 4+ Alum 30+ 



In this table the proportions are marked by integral numbers ; it being hard, 

 and perhaps unnecessary, to bring this matter to more exactness ; only to some 

 the sign + is added, to shew that those salts are stronger than the number in 

 the table by some fraction ; unless in the last 3, where the same sign imports 

 that the salt may be stronger by some units.* The tartar vitriolated is rated at 

 2 ; though more than 30 grs. of it was taken to equal the standard : but per- 

 ceiving it was not wholly dissolved, an allowance was made accordingly. On the 

 other hand, as part of the hartshorn flies off, its real force must be greater than 

 what appears by the table. The salt of amber is likewise volatile ; and as 3 grs. 

 of it were found more preservative than 6o grs. of sea-salt ; it may therefore be 

 much more than 20 times stronger. This is indeed an acid salt ; but as the acid 

 part of it is inconsiderable, this high antiseptic power must be owing to some 

 other principle. The sp. minder, was made of common vinegar and salt of harts- 

 horn ; the saline mixture of salt of wormwood saturated with lemon juice. The 

 alkaline part in either of these mixtures with water only, would have resisted 

 with a power of 4 + ; so that the acid added rendered these salts less antiseptic ; 

 viz. the sp. minder, by a half, and the saline mixture by a 3d part : which was a 

 circumstance very unexpected. 



Next he proceeded to try resins and gums, and began with myrrh. As part 

 of this substance dissolves in water, 8 grs. were made into an emulsion ; but 

 most of it subsiding, he could not reckon on a solution of more than 1 or 2 grs. 

 which nevertheless preserving the flesh longer than the standard, we may account 

 the soluble part of myrrh perhaps about 30 times stronger than sea-salt. 



Aloes, asa fetida, and the terra japonica, dissolved in the same manner as 

 myrrh, like it subsided, and with the same antiseptic force. But gum ammoniac 

 and sagapenum shewed little of this virtue : whether it was that they opposed 

 putrefaction less, or that all the antiseptic principle fell with the grosser parts to 

 the bottom. Three grains of opium dissolved in water did not subside, and 

 resisted putrefaction better than the salt. But more air than usual was gene- 

 rated, and the flesh became tenderer than with any of the stronger antiseptics. 



* Five grs. of borax was the smallest quantity compared with sea-salt ; but holding out so much 

 longer, he suspected 3 grs. would have been sufficient} in which case the force of this salt was to be 

 estimated at 20 : a singular instance of the strength of salt not acid. One grain of alum was weaker 

 than 60 grs. of sea-salt; but 2 grs. were stronger. The power therefore of alum lies between 30 

 and 60 ; but it seemed nearer the first number. — Orig. 



