Animal
Marvels of Pond-life Or, A Year's Microscopic Recreations Among the Polyps, Infusoria, Rotifers, Water-bears and Polyzoa
Powers that are most serviceable--Estimated by Focal length--Length of Body of Microscope and its Effects--Popular Errors about Great Magnification--Modes of Stating Magnifying Power--use of an "Erector"--Power of various Objectives with different Eye-pieces--Examination of Su...