122 Mr. Moyle on an Improvement in the Clinometer. [Feb. 



Article XII. 



On an Improvement of the Clinometer. By M. P. Moyle, Esq. 

 (To the Editor of the Annals of Philosophy.) 



SIR, Helslon, Jan. I, 1824. 



I have made an addition to the clinometer now generally in 

 use, which I flatter myself is an improvement; at least its utility 

 is more particularly felt in this neighbourhood by the superintend- 

 ants of mines in calculating the dip or underlie of a lode. Its 

 former construction pointed out only the angle from the horizon, 

 of any stratum, &c. I have now added another quadrant, on 

 which is delineated the number of feet and inches a lode will 

 underlie at certain angles in a fathom, perpendicular depth. The 

 following is an outline of the instrument. 



I find the underlie of a lode of one foot in a fathom will be 

 indicated by an angle of 80^° from the horizon, six feet in a 

 fathom at the angle of 45°, and so on. 



I am, Sir, your humble servant, 



M. P. Moyle. 



