"Bunsen's Burner, a form of gas burner especially adapted for heating, consisting of a tube, in which,…
"For a laboratory microscope, the pattern represented here has been found very convienient, —the…
"This picture is based upon a photograph of a painting which has won great fame during recent years.…
"Ruedorf's sand-bath, a simple form of sand-bath in which the temperature can be regulated by raising…