40 Reports and Proceedings. 
then appears of a uniform sediment and colour, and without any dis- 
tinct lamination. He wasinclined to the opinion that during deposition, 
the sand had been laid bare at regular periodic intervals and ex- 
posed to the chemical action of light and heat, and while thus 
exposed, a thin layer of the upper surface was bleached, and changed 
from its normal brown colour, producing the thin line of white, by 
the abstraction of the volatile bituminous ingredients, and that this 
surface was covered up afterwards by fresh deposits of brown sand. 
No current, he said, could spread over the area of deposit so thin 
and persistent a layer of white sand as this bed represented, repeated 
at so many distinct and periodic intervals, such as the specimens 
before them indicated. 
3. Mr. Joun DovGatt read a paper of some length, and of much 
interest, on ‘The Ancient Sea-margins and Raised Beaches around 
Glasgow.’ (To be noticed hereafter.) 
4. Mr. J. W. YounG, in presenting the Analysis of an undescribed 
Red Mineral from the Gleniffer Braes, said, that he believed Mr. 
John Young was the first to direct the attention of the members to 
this mineral, which is found in amygdaloidal porphyry. It is by no 
means peculiar to that locality, and occurs frequently in different 
varieties of trap-rocks. He had made a rough analysis about 
eighteen months ago, and was struck with the large pereentage 
(30 to 70) of iron-oxide which it contained. He had, however, now 
managed to make a full and careful analysis, and it gave him—water, 
4-66; silica, 21°33; magnesia, 5-26; and peroxide of iron, 6893. 
The specimen analysed was from porphyry of deep-red colour, and 
comparatively soft. If he might be allowed to propose a name for 
it, he would suggest ‘Ferrite,’ from the large percentage of iron it 
contains. Mr. John Young had obtained an analysis of a specimen 
from Langbank ; it has nearly three per cent. less of iron-oxide in it, 
but appears to be harder than the other. The chief difference in 
their composition appears to be that the Paisley specimens contain 
no lime, but magnesia; while the other contains lime but no 
magnesia. 
We have been favoured with the following note, and also with a specimen of the 
mineral, which may, we think, possibly prove to be pseudomorphous after felspar. 
—Ep. G. M. 
Remarks by Mr. John Young on the Mineral, from Gleniffer 
Braes, Paisley, analysed by Mr. J. W. Young, and proposed by 
him to be called ‘ Ferrite.’ 
This mineral occurs in several kinds of trap-rocks in the West of 
Scotland, in the deeper portions of which its crystals are of a 
blackish colour, often scarcely distinguishable from the dark base of 
the trap. Where the rock is porous, however, and the mineral has 
in consequence been affected by moisture or by the oxygen of the 
air, the crystals change to a bright deep red colour, which contrasts 
strongly with the dark colour of the stone. In this state they are 
softer, and the rock containing them becomes very friable. 
The crystals are regular in their form, and must have crys- 
tallized in the rock during the cooling of the mass. They do 
