22 * ADDITIONAL OBSERVATIONS. 
Quercitron. A crystalline substance then precipitates, 
which, while yet in suspension in the liquid, imparts to 
it a pearly appearance. It exhibits a slight acid re- 
action by curcuma-paper. It is slightly soluble in ether, 
but more completely so in alcohol. Water dissolves it; 
and the solution becomes orange-yellow by the addition 
of alkali. The acetate of lead and of copper, as well as 
the protochloride of tin, precipitate it in yellow flakes. 
Sulphate of the peroxide of iron colours it at first olive- 
green, and then causes a precipitate. Sulphuric acid 
dissolves Quercitrin, and the greenish orange coloured 
solution becomes cloudy by the addition of water. By 
dry distillation it yields, among other products, a liquid 
which soon crystallizes, the crystals possessing all the 
properties of Quercitrin. 
In the dyeing establishments the clear yellow colour 
is obtained by precipitating the tannin by means of a 
solution of glue or buttermilk; the colouring matter then 
remaining in the solution is mixed with the solution of 
alum and carbonate of potash, by which it is precipitated 
of a yellow colour in combination with the alumina. 
Protochloride of tin also produces with it a strong yel- 
low precipitate. 
Quercus rubra? The largest Red Oak in North 
America, says a correspondent of the Natchitoches 
Herald, can be seen on the plantation of W. Smith, Esq., 
eighteen miles from Natchitoches, on the road leading 
to Opelousas. This majestic Oak stands in the midst 
of a rich and heavy bottom, on the Bayou St. Barb. 
Two feet from the ground it measures forty-jour feet in 
circumference, and at six feet, thirty-two feet. The trunk 
appears sound and healthy, and its height, to the branches , 
is from fifty to sixty feet. 
