An inquiry into the propagation of contagious poisons, by the atmosphere

by Somerville Scott Alison

Plants, like animals, may be affected with disease, and may be most unwholesome, without exhibiting any very marked signs of their morbid condition.

DRINK.

Drink is as essential as food itself, to the maintenance of the health of man. Thirst is no less urgent than hunger itself, and it often happens that it must be satisfied when the calls of the appetite for food are unheard. Drink of a wholesome quality is highly salubrious, and conduces much to maintain the blood, and the various humours in a healthy condition. Water is the only beverage with which Providence has directly supplied his creatures, and is, under ordinary circumstances, the liquid of all others the best adapted to their use.

Pure water is refreshing, cooling, and dilutes the blood, which, without some diluent, would become too thick to move readily along its containing vessels, to perform aright its manifold duties, and to accomplish its numerous purposes in the animal economy. Water taken into the stomach goes to supply that very considerable part of the mass of blood which is constantly earned off in the shape of sensible and insensible perspiration, and of other secretions, and to correct the tendency in that vital fluid, to become irritating and acrimonious from the formation and accumulation of various salts.

In order that the deleterious action of some liquids may be the more readily understood, we will inquire how drink, which is taken into the stomach, is there disposed of.

One of the chief objects which is obtained from the use of drink, is the dilution and mollifying of the blood; and in order that this important purpose may be effected, it is necessary that they be brought in contact and mixed with each other.

Water, or any watery beverage, being received into the stomach, many thousand vessels open their mouths upon the walls of that organ, and imbibe the contained liquid, in virtue of a vital action which they possess. The liquid is soon sucked up, and is carried by the veins and the absorbent vessels into the general circulation, there to be mixed and incorporated with the mass of blood. It has been popularly thought, that there exists a direct communication between the stomach and the kidneys, by which the contents of the former are conveyed to the latter organs; and that supposition probably arose from the fact, that the kidneys have an immediate increase of duty after copious drinking; and that fluids having a peculiar and strong odour have been detected, discharged, very soon after their reception into the stomach.

However, there is no direct communication between these organs, and all liquids which are taken into the stomach must be passed through the general circulation before they can reach the kidneys; and thus it is worthy to be observed, that liquids which are possessed of deleterious properties, have an ample field for their operation.

It is rare that any bad effects follow the use of moderately cold water in a state of purity, and any instances in which injury has followed, may, with perfect propriety, be regarded as depending on accidental circumstances.

It sometimes happens, that water free of impurities, cannot be obtained, and that, what is highly impure is taken into the stomach. Many nations are occasionally subject to the privation of pure water, and are compelled to have recourse to the tainted waters of sluggish rivers, of almost stagnant rivulets, and putrefying lakes; and the consequence is, that their health suffers, and that the invasion of disease is much promoted.