PUBLICATIONS RECEIVED. 485 
gravity and other characters agree. It is the barytophyllite of Breithaupt, the 
masonite of Jackson and the sismondine of Delesse. All of these minerals occur 
in argillaceous, micaceous or chloritic slates and having a hardness of 5°0—6'0, 
and a density of 3-45—357. have been united with chloritoid, with which they 
agree in composition. (Dana, Mineralogy, ii. 298.) 
The phyllite of Thompson, according to the analysis of that chemist contains 
. a larger amount of silica than chloritoid together with more manganese, and 
6°80 p. c. of potash, but having had occasion to repeat several analyses of this 
chemist, I have found that his determinations of alkalies are entirely erroneous. 
Thus in the case of raphyllite a tremolite containing only traces of alkalies, he 
indicated more than ten per cent of potash and in his retinalite, a pure serpentine, 
nearly nineteen per cent of soda.* In both cases the error was at the expense 
of the magnesia of the mineral. The substance examined by Thompson has not 
so far as I know been examined or identified by American mineralogists, but in 
the mineralogical cabinet of Laval University at Quebec, is a specimen from the 
collection of the late Mr. Heuland ; said to be phyllite from Massachusetts, which 
is evidently chloritoid, and cannot be distinguished from the specimens of that 
mineral just described ; the rock is also apparently identical. 
The ottrelite of Haiiy, to which Dana has referred the phyllite of Thompson, 
occurs in an argillaceous slate in Belgium, and in a specimen before me cannot , 
be distinguished from the phyllite from Massachusetts or the chloritoid of Canada. 
This mineral has however been analyzed by Damour, whose name is a guarantee 
for accuracy, and differs from chloritoid in containing a considerable excess of 
silica, which might possibly be derived from the gangue. The specific gravity 
which Damour has assigned to ottrelite is 4:4—which is so extraordinary for & 
mineral of that composition that we are led to suspect some error probably of 
the press or pen. The question of the identity of ottrelite with chloritoid is one 
which requires farther examination. Meanwhile the latter mineral assumes some 
importance to the lithologist as characterizing over wide areas considerable 
masses of schists, which we have elsewhere described as chloritoid slate.” 
NOTICES OF BOOKS, &. 
Lovell’s General Geography. By J. George Hodgins, LL.B., Quarto, pp. 100, 
with numerous maps and illustrations. Montreal, J. Lovell; Toronto, R. & A. 
Miller. 1861. It must be well known to all engaged in the duties of tuition, 
that works compiled essentially for teaching purposes rarely succeed in meeting 
all the requirements of their special cases. Something is generally omitted or 
but slightly touched upon in this place, or too much elaborated in that; and 
treatises in which one would least expect it, are often made a vehicle for the 
Pn nnn nnn dL U EEE EEE SSSEEEEENEE 
* Report of Geol. Survey of Canada, 1850, p. 40. 
