288 Scientific Intelligence. 
compact dark red variety gave Deville, alumina 57:6, peroxyd of iron 
25°83, and water 10°8, besides 3-1 of titanic acid, and 2°8 of silica. In 
other specimens the proportions of alumina and iron oxyd are nearly 
iron, and 18 of alumina and titanium. In these analyses the carbonate 
of lime, generally present, was first removed by a dilute acid; the pro- 
longed action of stronger acids completely dissolves the hydrated oxyds. 
By an intense heat this substance is converted into crystalline corundum, 
resembling emery in its physical character, but the presence of grains of 
corundum in the hydrated mineral seems to show that this transformation 
ratures. T ery 0 : d 
Asia Minor, which is associated with variable proportions of oxyd of iron, 
is according to Dr. J. Lawrence Smith always more or less hydrated. 
_ The argillaceous matter enclosing some varieties of this bauxite oF 
impure diaspore, is white, without plasticity, and very rich in alumma,; 
one specimen freed from the red ferruginous portions, gave alumina 58'1, 
silica 21-7, peroxyd of iron 3°0, titanium 3-2, water 14-0. This substance 
ation 0 
organic matters, still require investigation. The careful examin pene 
iti 
unaltered sedimentary deposits, is calculated to throw great ad 
4, Note to the Paper of Messrs. Meek and Worthen on the Age of the 
Goniatite Limestone, p. 167 of this No.—The name “ Kinderhook Group : 
considered the equivalents of the Chemung Group of New York. Th} 
designation will be observed in the Illinois Report.—(Letter to Editors.) 
* Deville, Ann. de Chimie et Physique, (3) 1xi, 309. 
sl . 
+ In this connection we may noti patelite, a basic persulphate of irom, which 
occurs in conditions similar to aluminite 
5 
