STRUCTURE OF OOLITIC LIMESTONE. 
M. H. STILES, F.R.M.S. 
As an aid to the selection of a Limestone for the repair of our 
Parish Church (St. George’s, Doncaster), I recently examined 
several samples under the microscope. They were subsequently 
photographed, and the details are appended. All the samples. 
were from Rutland. 
No. 1, Casterton. In this case the oolitic granules are so 
loosely arranged that they are easily detached from the mass, 
and a surface suitable for photographing may readily be 
prepared by lightly grinding down a fragment on an ordinary 
stone sink moistened with water, washing, and subsequently 
I 2 3 4 
drying. The slight friction is quite sufficient to detach the 
granules without wearing away their surface. : 
With No. 2 from Edithweston this method does not answer, 
as the granules wear down and, to a great extent, lose their 
spherical form. Better results with stones of this character are 
obtained by chipping, and the selection of a piece with a fairly 
flat surface. Here the cohesion of the granules is sufficient 
to resist detachment in many cases, and consequently some of 
them are broken across in the process, as will be seen from the 
photograph. 
No. 3 isa sample of Ketton Stone. The granules are larger 
than those of the other samples, and the prepared specimen 
was so extremely beautiful when examined with a binocular 
microscope that I reproduced it as a stereogram. When 
viewed through a stereoscope the structure is exhibited in a 
very graphic manner. 
No. 41s an oolite from Clipsham, near Oakham, yielded by 
a new bed just drawn into working. There is a very marked 
Naturalist, 
