88 PHILOSOPHICAL TRANSACTIONS. [aNNO 1750. 



being pounded, 30 grs. of it proved fully as septic as the former. The same 

 powder was compared with an equal quantity of salt of wormwood, and care was 

 taken to shake both the mixtures alike: but after 3 days warm digestion, the salt 

 had neither tainted nor softened the flesh, while the chalk had rotted and con- 

 sumed that which was joined to it. Nor were the effects less of the testaceous 

 powders of the dispensary. Egg-shells in water resisted putrefaction, and pre- 

 served the meat longer firm than plain water.* 



1 1 . To try whether the testacea would also dissolve vegetable substances, he 

 infused them with barley and water, and compared this mixture with another of 

 barley and water, without the testacea. After a long maceration by a fire, the 

 plain water swelled the barley, became mucilaginous and sour; but that with the 

 powder kept the grain to its natural size, though it softened it, made no muci- 

 lage, and remained sweet. 



1 1. Nothing could be more unexpected than to find sea-salt a hastener of pu- 

 trefaction. But the fact is thus: 1 dr. of salt preserves 2 drs. of fresh beef, in 2 

 oz. of water, above 30 hours, uncorrupted, in a heat equal to that of the human 

 body ; or, what amounts to the same, this quantity of salt keeps flesh about 20 

 hours longer sweet than pure water ; but ^ dr. of salt does not preserve it above 

 2 hours longer. This experiment has been already mentioned. Now he after- 

 wards found, that 25 grs. have little or no antiseptic virtue; and that 10, or 15, 

 or even 20 grs. manifestly both hasten and heighten the corruption. -f- It is 

 moreover to be remarked, that in warm infusions with these smaller quantities, 

 the salt, instead of hardening the flesh, as it does in a dry form, in brine, or 

 even in solutions, such as our standard, it here softens and relaxes the texture of 

 the meat, more than plain water, though much less than water with chalk, or 

 the testaceous powders. 



Many inferences might be made from this experiment: but he only mentions 

 one. Salt, the indispensable seasoner of animal food, has been supposed to act 

 bv an antiseptic quality, correcting the too great tendency of meats to putrefac- 

 tion. But, since it is never taken in aliment beyond the proportion of the cor- 

 rupting quantities in these experiments, it would appear that salt is subservient to 

 digestion, chiefly by a septic virtue; that is, by softening and resolving meats; 

 an action very different from what is commonly believed.:}; 



* The trial was made with a coarse powder of this substance, but not repeated. — Grig. 



t The most putrefying quantity of salt, with this proportion of salt and water, is about 10 grs. 

 —Grig. 



I According to later physiologists, salt in small quantities proves subsen'ient to digestion, by its 

 stimulant action on the stomach; in the same manner as spices and other kinds of seasoning do. 



