SOME ROCK ANALYSES 29 



The leaves were taken from trees on the Cornell College 

 campus, or from the village of Mount Vernon. They were gath- 

 ered in the autumn and so were mature leaves. An analysis of a 

 sample of soil from the campus showed .1312 per cent of barium 

 sulphate. 



We desire to express our hearty thanks to Harold L. Maxwell 

 and Lester W. Rusk for making the analyses of this paper. 



SOME ROCK ANALYSES. 



NICHOLAS KNIGHT. 



I. A specimen from the Plains of Abraham. 



The rock was picked up on the Plains of Abraham, above Que- 

 bec, but came from a quarry in the neighborhood. The analysis 

 was made by Mr. 0. E. LaRue, and shows the rock to be a sand- 

 stone with a considerable admixture of Calcium and Manganese 

 Carbonates. The result is as follows : 



Per cent 



Si0 2 54.54 



Fe 2 3 5.37 



A1 2 3 6.64 



CaC0 3 , . . 15.12 



MnC0 3 18.33 



100.00 

 The specific gravity is 2.69. 



II. A specimen from the Alps. 



The rock was obtained from the Alps near Lucerne, Switzer- 

 land, and is used there as a building and road material. The 

 analysis by C. M. Peddycoart shows it is an impure limestone. 



Per cent 



Si0 2 11.81 



Fe 2 3 4.21 



A1 2 3 1.15 



CaC0 3 70.23 



MgC0 3 8.17 



H 2 4.26 



99.83 



