CHLORIDE OF SODIUM

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fully,” observes Moiroud ( Pharmac. Veterin. p. 410), “ to prevent, inthese animals, the influence of rainy seasons and wet pasturage, aswell as of damaged fodder. Given to animals intended for fattening, itgives more consistence to the fat and more taste to the meat.” It appeal'sto be offensive and injurious to many of the lower animals: hence whenrubbed on meat, it prevents the attack of insects, and when applied to theskin of leeches causes vomiting.

(c.) On man. —Chloride of sodium serves some important and essentialuses in the animal economy. It is employed, on account of its agreeabletaste, by the people of all nations, from the most refined to the most bar-barous ; but the quantity taken varies with different individuals, inasmuchas some have a much greater relish for it than others. It is, I think, notimprobable, that this unequal appetite for salt, in different individuals, isindicative of different wants of the system for this necessary substance;—for salt must serve some more important function than that of merely grati-fying the palate. It is an invariable constituent of the healthy blood. Dr.Stevens {On the Blood) has shown that the red colour of the blooddepends on the saline matters contained in it, for without these this fluidis black. Some of the properties of the sanguineous fluid, such as itsfluidity, its stimulating qualities, and its power of self-preservation, areprobably more or less connected with its saline constituents. The freehydrochloric acid found in the stomach, and which is so necessary todigestion, is probably derived from the salt taken in with the food,as is also perhaps the soda of the blood. The chloride of sodium foundin some of the secretions, as the bile and tears, probably serves someimportant purposes.

It is said that persons who take little or no salt with their food arevery subject to intestinal worms. Dr. Paris ( Pharmacologia ) tells usthat Lord Somerville, in his address to the Board of Agriculture, statesthat the ancient laws of Holland “ ordained men to be kept on breadalone unmixed with salt, as the severest punishment that could beinflicted upon them in their moist climate; the effect was horrible: thesewretched criminals are said to have been devoured by worms engenderedin their own stomachs.” Mr. Marshall {Med. andPhys. Jour. vol. xxxix.)tells us of a lady who had a natural aversion to salt: she was mostdreadfully affected with worms during the whole of her life.

Considered in a therapeutical point of view it is an irritant in its localoperation. Thus applied to the skin and the mucous membranes itcauses redness. Taken into the stomach in large quantity (as in the doseof a table-spoonful or more) it excites vomiting, and when thrown into thelarge intestines produces purging. In moderate quantities it promotesthe appetite, and assists digestion and assimilation. If used too freely itoccasions thirst. The long-continued employment of salted provisionsoccasions scurvy: of the correctness of this statement there cannot exist,I think, a shadow of doubt, notwithstanding the bold denial given to itby Dr. Stevens {op. cit. p. 262); a denial the more remarkable, since Dr.Stevens admits he has never seen a single case of the disease ! Hisopinion is evidently founded on hypothetical grounds, and is in directopposition to the best medical testimony we possess.

In some diseases the moderate use of salt produces the effects of a tonic.It acts as a stimulant to the mucous membranes, the absorbent vessels,