The various utensils used for the preparation and keeping of food are made either of metal, glass, pottery ware, or wood; each of which is better suited to some particular purposes than the others. Metallic utensils are quite unfit for many uses, and the knowledge of this is necessary to the preservation of health in general, and sometimes to the prevention of immediate dangerous consequences.

The metals commonly used in the construction of these vessels are silver, copper, brass, tin, iron, and lead. Silver is preferable to all the others, because it cannot be dissolved by any of the substances used as food. Brimstone unites with silver, and forms a thin brittle crust over it, that gives it the appearance of being tarnished, which may be accidentally taken with food; but this is not particularly unwholesome, nor is it liable to be taken often, nor in large quantities. The discoloring of silver spoons used with eggs arises from the brimstone contained in eggs. - Nitre or saltpetre has also a slight effect upon silver, but nitre and silver seldom remain long enough together in domestic uses to require any particular caution.

Copper and brass are both liable to be dissolved by vinegar, acid fruits, and pearl-ash. Such solutions are highly poisonous, and great caution should be used to prevent accidents of the kind. Vessels made of these metals are generally tinned, that is, lined with a thin coating of a mixed metal, containing both tin and lead Neither acids, nor any thing containing pearl-ash, should ever be suffered to remain above an hour in vessels of this kind, as the tinning is dissolvable by acids, and the coating is seldom perfect over the surface of the copper or brass.

The utensils made of what is called block tin are constructed of iron plates coated with tin. This is equally to be dissolved as the tinning of copper or brass vessels, but iron is not an unwholesome substance, if even a portion of it should be dissolved and mixed in the food. Iron is therefore one of the safest metals for the construction of culinary utensils; and the objection to its more extensive use only rests upon its liability to rust, so that it requires more cleaning and soon decays. Some articles of food, such as quinces, orange peel, artichokes, &.c. are blackened by remaining in iron vessels, which therefore must not be used for them.

Leaden vessels are very unwholesome, and should never be used for milk and cream, if it be ever likely to stand till it become sour. They are unsafe also for the purpose of keeping salted meats.

The best kind of pottery ware is oriental china, because the glazing is a perfect glass, which cannot be dissolved, and the whole substance is so compact that liquid cannot penetrate it. Many, of the English pottery wares are badly glazed, and as the glazing is made principally of lead, it is necessary to avoid putting vinegar, and other acids into them. Acids and greasy substances penetrate into unglazed wares, excepting the strong stone ware; or into those of which the glazing is cracked, and hence give a bad flavor to any thing they are used for afterwards. They are quite unfit therefore for keeping pickles or salted meats. Glass vessels are infinitely preferable to any pottery ware but oriental china, and should be used whenever the occasion admits of it.

Wooden vessels are very proper for the keeping many articles of food, and should always be preferred to those lined with lead. If any substance has fermented or become putrid in a wooden cask or tub, it is sure to taint the vessel so as to make it liable to produce a similar effect upon any thing that may be put into it in future. It is useful to char the insides of these wooden vessels before they are used, by burning wood shavings in them, so as to coat the insides with a crust of charcoal.

As whatever contaminates food in any way must be sure, from the repetition of its baneful effects, to injure the health, a due precaution with respect to all culinary vessels is necessary for its more certain preservation. There is a kind of hollow iron ware lined with enamel, which is superior to every other utensil for sauces or preserves: indeed it is preferable for every purpose