149 
CHEMICAL NOTES ON LAKE DISTRICT ROCKS. 
Il.—INTRUSIVE AND SEDIMENTARY ROCKS. 
ALFRED HARKER, M.A., F.G.S., 
St. John’s College, Cambridge, 
In the former part of this paper I have collected the available 
chemical data relative to the ‘contemporaneous’ or bedded 
volcanic rocks, lavas and tuffs, of the Borrowdale Series. 
I proceed now to perform a like office for the intrusive rocks 
of the district, though here I have but little to add to the 
information already published. 
While some of the intrusions are probably of Ordovician age 
and connected with the same period of igneous activity as the 
volcanic series which they often traverse, others certainly belong 
to later dates. The granites and the lamprophyres, for instance, 
must be referred to the Old Red Sandstone period, or at least to 
the interval between the Silurian and the Old Red Sandstone, 
while the Carrock Fell rocks, and perhaps certain others, may — 
be still younger. In the case of many of the minor intrusions 
it is scarcely possible to obtain any direct evidence as to their 
precise age. 
Beginning with the granites and allied rocks, we have five 
complete analyses by Mr. J. Hughes of the principal masses of 
acid intrusive rocks in the districts. The silica-percentages, 
quoted from Clifton Ward’s papers,* are given under the 
numbers (61), (62), (71), (72), and (80). Of the Shap granite 
Ward gave no analysis, but three complete analyses by Dr. J. B. 
Cohen, (67) to (69), and two ia aspen by Mr. E. 5: 
Garwood: (66) and (70), are given in a paper on that rock by 
Harker and Marr.+ Nos. (63) to (65) and (73) to (79) are from 
a paper by the present writer on the Carrock Fell granophyre 
and the Grainsgill greisen.{ Of these, (65) and ua are from 
complete analyses by Mr. L. J. Spencer and Mr. G. Barrow, 
respectively, while the rest are pre hse only. 
Nos. (63), (76), and (79) were made by Messrs. W. A. Brend 
and E. H. Cunningham Craig; (64) in the laboratory of Owens 
* Quart. Journ. Geol. Soc., vol. xxxi., p. 597, 1875; vol. XXXIL., pp. 5, 75 
22-24, 1876, 
+ Ibid, vol. xlvii., pp. 275, 276, 278, 280, 1891. 
+ Ibid, vol. li., pp. 125-147, 1895. 
May i899. 
