Outlines of a course of lectures on medical jurisprudence / by Thomas Stewart Traill.

  • Traill, Thomas Stewart, 1781-1862.
Date:
1840
Catalogue details

Licence: Public Domain Mark

Credit: Outlines of a course of lectures on medical jurisprudence / by Thomas Stewart Traill. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    with enamels, will not obviate the danger, because enamels are very liable to crack when heated, and thus expose the surface of the copper to acescent food. Since the disco- very of laminating zinc, this metal has been much employ- ed as vessels for the dairy, for cisterns, and water-pipes. Zinc easily oxidates, but this defends the surface against further action; and except for acid food, or where heat is employed, such vessels are useful and wholesome. They are said to cause cream to separate more readily from milk than earthenware vessels ; and they are more easily kept clean, and are lighter than wood. Zinc, on account of its lightness, is much employed instead of lead, on roofs, and for pipes to carry off water. It answers well for these pur- poses, and is not dangerous, but it is not lasting. The ob- jection to vessels of tinned iron is their little durability, and the lead solder with which they are put together. Vessels of iron are durable and cheap, but they blacken some kinds of food; this is best obviated by a coating of tin. Vessels of gold and silver are far too expensive for ordinary use ; but copper is often covered with a thin plate of silver, forming what is termed plated ware, which is ex- cellent while the silver remains on the copper. A thinner coat of silver is applied, in some instances, by means of an amalgam of silver, and a similar process is commonly used to gild the inside of silver or of plated ware. What has been termed German silver, is made of various alloys of copper and other metals, as with tin and antimony, or with nickel. This has nearly the splendour of real silver; but is readily acted on by acids, and therefore not suited for culinary purposes, even if it could be had at a cheap rate. Pottery is a valuable addition to culinary utensils. It is of all qualities, from the purest porcelain of China or of Europe, to the coarsest earthenware. The glazes which contain lead are objectionable, where acids are to be used, but if well baked, such glazes are not readily acted on. In La Mancha in Spain, much use is made of coarse