ov 
columnite by means of the microscope he has been enabled to 
ascertain that the “ flexibility is due to small and innumerable 
ball and socket joints which exist throughout the mass of the 
stone very uniformly. Each joint permits a slight movement 
which is always greater in one direction.” Now I must say 
that, though I have come to the investigation prepared with 
considerable faith, yet, after many careful examinations, I 
was never able to force my imagination to the extent of get- 
ting it to show me anything resembling ball and socket joints. 
The examination need not always be made of the opaque 
sandstone, but portions can be roughly crushed and mounted 
in Canada Balsam so that light may be transmitted through 
them and the mode of their interlocking plainly made 
evident. The fact is that the rock is made up of small, 
broken, irregular masses of transparent sand which evidently 
have not been carried any great distance by water, as their 
sharp edges have not been at all abraded, but, on the contra- 
‘ry, remain, but they have evidently been broken off from a 
rock which had a conchoidal fracture, they being little plates 
of extremely irregular outline. Thus when théy settled in 
the liquid in which we can suppose them to be thrown down 
they naturally, for the most part, distributed themselves with 
their greatest axes in the same direction, and hence the lamina- 
tion and cleavage of the rock itself We can readily 
understand that in such a rock, if the particles were not 
strongly held together, that they would possess a certain 
amount of motion one over the other, and this motion would 
be most marked in a direction at right angles to the lamina- 
tion, which is the case. But, also, such a rock would not be 
elastic, only flexible, and gradually, after several times bend- 
ing, be broken. Such is exactly the case with Itacolumnite. 
In fact any one possessing a microscope and a fragment of 
this rock, can readily verify my observations and demonstrate 
that Dr. Wetherill’s proposed name of Articulite is inappro- 
priate for Itacolumnite. In conclusion, I would mention that 
grains of the crushed rock when put up in Canada Balsam 
become very beautiful objects for examination by means of 
