490 



Chemical Analysis of Tahasheer. 



[Oct. 



According to Hamilton, the Vateria Indica produces the gum anime 

 which Dr. Roxburgh says is termed i : i eomm rce, East Indian Copal. 

 Schindler tells us that there are three kinds of Copal ; I. The East 

 In Wan, or African Copal, is the brightest and softest, and affords the 

 best varnish. It is sometimes called ball copal. % The second variety 

 is called West Indian or American Copal, being derived from the An- 

 tilles, Mexico, and North America, and is procured, according to Mar- 

 tius and Hayne, from different species of Hymenea, Track ylobium, and 

 Vouapa. It is termed stone copal, and is yellower than the preceding 

 kind. It comes to us in hard, flat pieces, weighing about three ounces. 

 It is less easily melted than the preceding variety, and seldom contains 

 insects. 3. The third variety is also termed West Indian copal, but 

 might be mistaken for the first species, as it occurs in the form of 

 convexo-concave pieces, eight ounces in weight. Taste aromatic. 

 Melting point between that of the two preceding. Fresh oil of rose- 

 mary dissolves the first in any proportion. Fresh oil of turpentine 

 dissolves the first variety completely, but only dissolves a small portion 

 of the other two, after long digestion. The action of alcohol is similar. 

 Schindler terms the last species, for the sake of distinction, insect, copal. 



These facts I consider it proper to bring forward, because Dr. Ha- 

 milton denies that copal comes from India. Now, this opinion is at 

 variance with the statement of Retzius, who called it Blaeocarpus copal- 

 liferus, because it afforded the gum copal. Dr. Roxburgh alleges also 

 that the resin of the Paenoe is called East India copal. Mr. Turnbull 

 of Mirzapour informed Dr. Hamilton that some which he sent home 

 for trial would not sell for copal, although it was allowed to be anime. 

 " The real copal and anime," he adds, " are American productions." 

 The resin of the Paenoe, or Dupa (Vatena Indica) was probably 

 used by the Brahmans of Malabar as an incense. The Paenoe is one 

 of the finest ornamental trees in India ; and in the province of Canara 

 it is usually planted in rows by the sides of highways, making remark- 

 ably fine avenues. The statement of Mr. Turnbull is not conclusive, 

 because he does not state that its rejection was the consequence of 

 chemical examination. — Records of General Science, for October, 1835. 



Chemical Analysis of Tabasheer. By Thomas Thomson, m. d., 

 f. r. s., l. and e., &c, Regius Professor of Chemistry in the Uni- 

 versity of Glasgow. 



Having lately received, from Calcutta, a very fine specimen of 

 tahasheer, I was naturally induced to make a few experiments on its 

 chemical constitution. 



