Page:Willich, A. F. M. - The Domestic Encyclopædia (Vol. 3, 1802).djvu/452

428&#93; 42B] POR period, be converted to more irii- portant purposes. — Horses, cows, goats, and swine, refuse to eat this herb. From the saffron-coloured juice of the Greater Celandine, no perma- nent colour could be obtained in the experiments made by conti- nental dyers ; but, according to the assertion of Rossig, a reputable German author, the whole plant produced, by fermentation, a good bii^s-colonr, similar to that obtain- ed from WoAD, or the Isatis tinc- taria, L. ; a faA well deserving the attention of dyers. 2. The cornuulatum (Glauciiim pheenicium of Dr. Smith), Red Horned-Poppy, or Red Celan- dine, is found in corn-fields, in the county of Norfolk : its reddish flowers appear in the months of July and August. — ^I'his species is cultivated in gardens for the beauty of its flowers ; but the whole plant is an acrid and narcotic poison. PORCELAIN, orCHiNA-WARE, a most refined, and almost vitre- fied, species of earthen-ware, which is not only manufa6tured in China, but likewise ii) England, France, Holland, and Germany : the most esteemed and beautiiul, both for its painting, and the taste displayed in shape and figure, is that imported from Meissen, in Upper Saxony. As a detail of the manner in ^vhich porcelain is manufadtured, Avouid be foreign to our plan, we •shall coucijcly relate the simple, but valuable, method of converting common green glass into porce- lain, discovered by M. Reaumur. It consists in exposing such glass, surrounded with wliite sand, piaster of Paris, chalk, or gypsum, in a luted crucible, to a degree of heat equal to. that of potters' fimiaces. POR so as not to alter its form or shape* At first, it will assume various shades of blue ; become gradually white ; and, at length, no appear- ance of glass will remain. By this process, entire green bottles and other vessels may be converted into the finest china-ware. Porcelain, if not properly an- nealed, is exti^emely brittle, and liable to crack : to prevent such ac- cidents, it ought to be well boiled in pure water, before it is used ; and, when cold, no hot fluid should be put into it, unless there be some sugar, or a tea-spoon in the vessel. Another method of obviating casu- alties, is that of holding cliina-ves- sels over steam, immediately before tea or coffee is poured into them. Such accidents, however, often de- face the beauty, or otherwise dimi- nish the value of a set of china : hence, it becomes a desirable ob- jeirf to join or cement the frag- ments, so as to be imperceptible to the naked eye. Under the article Cement, and likewise on other occasions (for which the reader is ref rred to the General I/ider of Reference), we have stated the most proper expedients for this purpose : we shall therefore only remark, that all china-ware, im- ported by the East-India Company, pays 2l. per cent, on being depo- sited in their warehouses : and is subject to the farther prohibitory duty of IO9I. 8s. 6d. per cent, ac- cording to its value, when taken out for domestic use. PORK, is the flesh of bogs, kill- ed for culinary purposes. Having already, in the article Hog, treated of the relative saki- brity of Uiis aliment, when eaten in a fresh state 5 and likewise stat- ed the best mode of preserving meat