44 Whitney's. Chemical Examination 
tive proof that it is not titanic acid in combination with a 
base, since all the known titanates are soluble in acids. How 
Prof. Shepard was led to suppose the mineral to be a niobate 
of yttria and thorina, I am unable to explain. Its specific 
gravity alone is sufficient proof that such could not be its 
composition. 
This is then a new form of Brookite, and as such, interest- 
ing, especially as it has the color and opacity of nigrine, 
(variety of rutile) with the crystalline form and specific gravity 
of the former mineral. 
Il. OZARKITE. 
This mineral from the same locality as the former, Magnet 
Cove, Hot Springs Co., Arkansas, is not a crystallized sub- 
stance, but forms a thin coating on eleolite, or small ovoidal 
masses in it; it being, as described by Prof. Shepard; con- 
stantly separated from this mineral by a thin layer of a reddish 
substance. 
It seems hardly worth the while to contend the claim to 
rank as a new species of a substance of which no analysis is 
given, which merely forms a thin amorphous incrustation on 
another, and the purity of which we have no means of ascer- 
taining ; it would be sufficient to say that no substance, unless 
evidently crystallized in a new form, can be allowed to be new 
till it has been proved to be such by accurate analysis. Prof. 
Shepard says, without giving any reasons, that it appears to 
be “a silicious hydrate of lime and yttria, possibly also having 
traces of thorina." 
On separating a portion of this mineral as pure as possible, 
and testing it before the blow-pipe, I find that it fuses with 
great facility, intumescing slightly, like a zeolite, and having 
a tendency to swell up with vermicular contortions like meso- 
type or scolezite. It colors the flame yellow, indicating the 
presence of soda, and emits a brilliant light like a silicate of 
lime. : ‘ | 
It is readily dissolved by acids to a clear liquid, a reac- 
