Salt appears to be a necessary and universal stimulus to animated beings; and its effects upon the vegetable as well as animal kingdom have furnished objects of the most interesting inquiry to the physiologist, the chemist, the physician, and the agriculturist. It appears to be a natural stimulant to the digestive organs of all warm-blooded animals, and that they are instinctively led to immense distances in pursuit of it. This is strikingly exemplified in the avidity with which animals in a wild state seek the salt-pans of Africa and America, and in the difficulties they will encounter to reach them: this cannot arise from accident or caprice, but from a powerful instinct, which, beyond control, compels them to seek, at all risks, that which is salubrious. To those who are anxious to gain further information upon this curious subject, I would recommend the perusal of a work entitled "Thoughts on the Laws relating to Salt, by Samuel Parkes, Esq.," and a small volume by my late lamented friend, Sir Thomas Bernard, on the "Case of the Salt Duties, with Proofs and Illustrations." We are all sensible of the effect of salt on the human body; we know how unpalatable fresh meat and most vegetables are without it.

During the course of my professional practice, I have had frequent opportunities of witnessing the evils which have attended an abstinence from salt. In my examination before a committee of the House of Commons in 1818, appointed for the purpose of inquiring into the laws respecting the salt duties, I stated, from my own experience, the bad effects of a diet of unsalted fish, and the injury which the poorer classes, in many districts, sustained in their health from an inability to procure this essential condiment. I had some years ago a gentleman of rank and fortune under my care, for a deranged state of the digestive organs, accompanied with extreme emaciation. I found that, from some cause which he could not explain, he had never eaten any salt with his meals: I enforced the necessity of his taking it in moderate quantities, and the recovery of his digestive powers was soon evinced in the increase of his strength and condition. One of the ill effects produced by an unsalted diet is the generation of worms. Mr. Marshall has published the case of a lady who had a natural antipathy to salt, and was in consequence most dreadfully infested with worms during the whole of her life. - (London Medical and Physical Journal, vol. xxix.

No. 231.) In Ireland, where, from the bad quality of the food, the lower classes are greatly infested with worms, a draught of salt and water is a popular and efficacious anthelmintic. Lord Somerville, in his Address to the Board of Agriculture, gave an interesting account of the effects of a punishment which formerly existed in Holland. "The ancient laws of the country ordained men to be kept on bread alone, unmixed with salt, as the severest punishment that could be inflicted upon them in their moist climate. The effect was horrible; these wretched criminals are said to have been devoured by worms engendered in their own stomachs." The wholesomeness and digestibility of our bread are undoubtedly much promoted by the addition of the salt which it so universally receives l. 186. If the utility of salt be thus established, it may be asked, how it can happen that salted provisions should ever produce those diseases which experience has shown to arise from their use? It is true that a certain proportion of this condiment is not only useful but indispensable: but an excess of it is as injurious as its moderate amplication is salutary.

This observation applies with as much force to the vegetable as to the animal kingdom; a small proportion, applied as a manure, promotes vegetation in a very remarkable manner; whereas a larger quantity actually destroys it. The experiments of Sir John Pringle have also shown, that a little salt will accelerate putrefaction, and a large quantity prevent it. In explaining the operation of salting meat, and in appreciating the effects of such meat as food, it will be necessary to advert to a chemical fact, which has not hitherto attracted the attention which its importance merits. The salt thus combined with the animal fibre ought no longer to be considered as the condiment upon which so much has been said; a chemical combination has taken place; and, although it is difficult to explain the nature of the affinities which have been brought into action, or that of the compound to which they have given origin, it is sufficiently evident that the texture of the fibre is so changed as to be less nutritive, as well as less digestible.

If we are called upon to produce any chemical evidence, in support of such an assertion, we need only relate the experiment of M. Eller, who found, that if salt and water be boiled in a copper vessel, the solution will contain a notable quantity of that metal; whereas, if, instead of heating a simple solution, the salt be previously mixed with beef, bacon, or fish, the fluid resulting from it will not contain an atom of copper. Does not this prove that the process of salting meat is something more than the mere saturation of the animal fibre with muriate of soda?

1 A pound of salt is generally added to each bushel of flour. Hence it may be presumed, that every adult consumes two ounces of salt per week, or six pounds and a half per annum, in bread only.

187. The beneficial operation of salt as a condiment is proved by ample experience: theory has had no share in establishing the fact; and, in the present state of our physiological knowledge, it will be, perhaps, difficult to offer a theory for its explanation. It may probably only operate as a stimulant upon the alimentary passages, although, to those who are disposed to place any confidence in the views already stated (109), an hypothesis will necessarily suggest itself, which, on the present occasion, it is not my intention either to support or to invalidate.