His largest instrument a 12-inch photo lens, he made himself, and the method he uses for photographing asteroids is one of his own devising, which permits successful work with much smaller instruments than those required by the old methods. His skill as a lens grinder is the result of necessity, dating back to his early studies, when he first began experimenting and had to learn by bitter experience. For the largest one he has ever made, the 12-inch lens he now uses, tested disks were imported from Paris and the curves computed by Prof. F. R. Moulton of Chicago. His observatory is of very simple construction. It is made in two parts, one half a little larger than the other, so one slides over the other about six inches when the roof is closed.
Grooves run up and down at the joint of the lower section to prevent water working in.
The sections of the roof are each mounted on four wheels, which run on an iron track fastened to the long beams, which are twice the length of the house. The roof is opened by pulling two ropes fastened in the middle of the cross-pieces of the projections. He has also made a measuring machine for astronomical photographs. It holds a larger plate than the Oxford and Greenwich machines, and differs slightly in the lens and micrometer scale. He bought a Troughton Simms micrometer scale and a Teiss Planular doublet for microscopic enlargement and a Teiss micrometer scale.