THE SYENITES OF SOUTH LEICESTERSHIRE. 
41 
THE SYENITES OF SOUTH LEICESTERSHIRE. 
By W. Jerome Harrison, F.G-.S. 
(Continued from page 11.) 
General Conclusions .—Having now examined all the points 
at which these syenitic rocks crop out in South Leicester¬ 
shire, we may briefly sum up, and point out the conclusions 
derivable from a minute study of the rocks and the conditions 
under which they occur. 
(1) The rock, in all the exposures, has a general simi¬ 
larity, so that it is difficult to tell from which pit any hand 
specimen came. It is a syenite, a crystalline, unstratified, 
unfossiliferous rock, all of which facts clearly point to its 
being igneous or fire-formed— i.e., it has been melted, and has 
slowly cooled down. Whether the differently coloured, finer- 
grained masses, so often seen included in the syenite, may 
not be lumps of some older rock—perhaps slate—which the 
syenite has enveloped, incorporated, and altered—is a very 
interesting question. The remarkable specimen alluded to, 
from Cauver Hill Quarry, might certainly seem to point in 
this direction. 
(2) As to the age of the rock. It is clearly connected with 
the Charnwood Forest Series; the coarse slate seen in 
Enderby Quarry belongs either to the Charnwood Pre- 
Cambrian Beds or to the Cambrian strata which we now 
know to rest upon them. If we could strip off the red 
marls we should find these old Palaeozoic rocks forming an 
uneven land surface and connected with the equally old, 
or older rocks of Groby and Markfield ; in fact, at a point 
about half way, called “ Baron’s Park,” near Kirby Muxloe, 
it is reported that syenite was struck in a boring at a depth 
of 118 feet. This underground extension of the Charnwood 
Rocks forms the easterly boundary of the Leicestershire coal 
field, whose coal seams rise up against it along a line extend¬ 
ing from Desford to Hinckley. At a point called Sapcote 
Freeliolt, about two miles east of Hinckley, on the land of 
the late Mr. T. Frewen, a boring executed by Mr. J. A. 
Boswortli, F.G.S., passed through about 540 feet of red 
marls. At this depth it entered hard slates, which were 
penetrated to the great depth of 1,655 feet. All the slaty beds 
were standing up on end, marking the position of a boundary 
line close to and on the east, this boundary line being formed 
by the ridge of igneous rocks whose exposed summits we have 
been describing. We must refer these slates to the Cambrian 
formation, whose presence in the immediate vicinity (between 
