Pewter
2 of the 7 encyclopedias on this shelf carry an entry for Pewter. Both are reproduced below, so you can see where they agree and where they differ.
The Encyclopedia of Founding (1892)
Important: Safety Warning This page describes trade processes that use dangerously toxic materials such as cyanide solutions, mercury amalgams, or strong acids. These processes require training, equipment, and precautions far beyond what the text describes. In addition, this page describes additives or treatments for food or drink that are now known to be toxic and are prohibited in food today. This information has been left in for historical purposes but should not be acted upon. A useful alloy of tin and lead. The common or ley-pewter is 4 tin and 1 lead; plate-pewter, 100 tin, 8 antimony, and 2 each of bismuth and copper; trifle-pewter, 83 tin and 17 antimony. The best pewter is composed of 100 parts tin and 17 antimony. A very hard pewter is 192 tin, 16 antimony, and 4 copper. Tin-and-temper pewter is the best, and is made as follows: Let a "temper" be made from 2 parts tin and 1 part copper, and to every pig of tin weighing about 375 pounds add from 1 to 7 pounds of the temper. See PEWTERER'S TEMPER; TIN; ANTIMONY.
Aiton's Encyclopedia (1910)
Important: Safety Warning This page gives an alloy formula containing lead and specifies it for mugs, plates and tableware. Lead migrates from such vessels into food and drink and causes cumulative poisoning; it is prohibited in food-contact metal today. This information has been left in for historical purposes but should not be acted upon. pu'ter, an alloy of four parts of tin with one of lead. Known also as Britannia metal. It stands more heat and is firmer than either metal alone. It is used chiefly for mugs, plates, and cheap tableware. An alloy known as plate-pewter consists of ninety parts of tin to eight parts antimony, and two parts each of bismuth and copper. Still a third pewter is composed of eighty-three parts tin and seventeen parts antimony.