III. Several microscopical observations and experiments, made by Mr. Stephen Gray

Abstract

Having not long since attempted to make some of these Microscopes, which Mr. Butterfield describes and instructs to make,in the Philosophical Transactions, N° 141. P. 1026. of the manner then lately brought out of Holland by Mr. Hugens ; but for want of such a Lamp, as the before named Person mentions, I proceeded after a some what different Method.