All kinds of water, especially rain and the softer waters, are apt, if contained in imperfectly closed leaden vessels, to corrode and become impregnated with this metal. Such contamination is indicated by the surface of the water being covered with a thin white film, and the sides of the tank or pipe with a similar incrustation. The impregnation of water with lead is fortunately of not very frequent occurrence, but, when it does take place, is productive of serious consequences; diseases, assuming almost the character of epidemics, have been traced to this cause. Dr. Combe cites the instance of the citizens of Amsterdam, who about the middle of the last century suffered severely from disease induced by the substitution of lead for tiles on the roofs of the houses, through which the rain-water, which is generally used by them for culinary purposes, was rendered poisonous. "In 1814, the inhabitants of Tunbridge suffered in like manner from colic, owing to the town being supplied with water which passed through a course of lead pipes for a quarter of a mile : the malady disappeared when iron pipes were substituted."

Water is of all drinks the least objectionable, and that best adapted to the wants of the system. If taken in moderation, it interferes in no way with the function of digestion; it supplies the loss of fluid constantly taking place, and its action is neither stimulating nor depressing. Waterdrinkers can reckon among their number a large proportion of those who have attained to extreme longevity, and who, at the same time, have exhibited sustained physical and intellectual

vigour. For individuals of sanguine temperament, and for the inhabitants of hot climates, water is better adapted than any other liquid. Persons are very apt, on moving to any new locality, to attribute certain effects produced upon them to difference in the air; such effects are, however, generally due to the water, the ingredients of which vary with the different sources from which it springs. The water of Paris and of other continental towns is peculiarly hard, and seldom fails to affect Englishmen who drink it for the first time.

It is a remarkable fact, that certain fluids have ever been in request among different nations for the effect they produce upon the nervous system and brain, and through these upon the intellectual faculties. Tea, coffee, chocolate, and Paraguay tea, or maté, are still eagerly sought after by man in different parts of the world. The Chinese imbibes the pure infusion of tea-leaves after every meal, and probably attributes to its qualities the conceived superiority of his own over other races; the Arab and the Turk sip their coffee, and find in its stimulating action a pleasing substitute for the excitement of spirituous liquors, from which they are debarred by their religion; the South American sucks in his maté, and his mind is alternately lulled and brightened by its influence. For the last two centuries, moreover, the use of tea and coffee has extended to other countries than those in which they are indigenous -to Europe, America, and indeed to every part of the earth. The liquids prepared from these plants may be said to exercise not a little influence upon the intellectual life of civilized man. The French

man's vivacity is brightened and his imagination warmed by the cup of strong coffee which he imbibes immediately after a meal; the Englishman, rendered torpid by the concentration of his nervous energy upon the digestion of a full dinner, is again roused to life and action by one of these liquids. Independently of their effect upon individuals, tea and coffee take even a higher position in the social influence they have exerted upon communities. The tea-table is still the rallying point towards the close of the day in most English families, and especially so with those who adopt the system of total abstinence from spirituous liquors. Coffee and chocolate houses were the principal places of resort with all classes in the first half of the last century. Certain of these establishments were frequented by literary characters, some by politicians of the Whig, others by those of the Tory party, some by merchants, others again by the aristocracy. Will's coffee-house is well known to have been the place of rendezvous for the wits and poets of the period, and to have owed its reputation to the patronage of Dryden; it was also frequented at a later date by Johnson. The Spectator, in one of his papers, says, "I first of all called in at St. James's, where I found the whole outward room in a buzz of politics. The speculations were but very indifferent towards the door, but grew finer as you advanced to the upper end of the room, and were so very much improved by a knot of theorists, who sat in the inner room, within the steams of the coffee-pot, that I there heard the whole Spanish monarchy disposed of, and all the line of

Bourbon provided for, in less than a quarter of an hour."

These drinks-tea, coffee, chocolate, and Paraguay tea-whose reputation is so general, and action so similar, owe their characteristic properties to the presence of a peculiar principle, which, in one and all, is nearly identical, and which, further, is supposed to be restricted to the plants from which these liquids are prepared. This fact would seem to show that these liquids are had recourse to for no mere idle gratification, but that they really supply a want in the physical life of man.

Tea is the general drink in Oriental Asia, having been used in China and Japan-to which countries it is probably indigenous-from time immemorial. It is now extensively used in Europe, especially by the English and Dutch, and in America. It was brought to Europe in 1602, by the Dutch East India Company, and to this country, from Holland, in 1666. When first introduced into England, its use was limited to the very opulent, as will readily be conceived, when it is stated that it then sold for sixty shillings a-pound. It is now within the reach of all classes, and rich and poor alike court its soothing influence.

Tea is the produce of a plant belonging to the genus Thea, placed by Jussieu in the same family with the orange-tree, by Decandolle in the family of the camellias. At any rate, the tea-plant, when in flower, can scarcely be distinguished from a species of camellia. From the jealousy exhibited by the Chinese in reference to the plant, it was found almost impossible, until lately, to determine

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