It forms microscopic hexagonal plates having a silver-white streak.
Experiments on alloys are, in some ways, easier to make than on pairs of non-metallic substances, partly owing to the possibility of polishing sections for microscopic examination, and the investigation of alloys has done much to elucidate the general phenomena of solution, of which metallic solution constitutes a special case.
The investigation of the microscopic pelagic life of the sea has also developed to a great extent.
His chief work was in microscopic petrology, to the study of which he was attracted by the investigations of Dr H.
Occurrence of a food-reserve; many so-called exalbuminous seeds show to microscopic examination a distinct endosperm which may have other than a nutritive function.
Deeper than this, microscopic life is scanty; there is practically no reproduction and growth.
The experiment of Engelmann referred to deserves to be mentioned here, if only in illustration .of the use to which algae have been put in the study of physiological problems. Engelmann observed that certain bacteria were motile only in the presence of oxygen, and that they retained their motility in a microscopic preparation in the neighbourhood of an algal filament when they had come to rest elsewhere on account of the exhaustion of oxygen.
As the microscopic character of the corallum of these extinct forms agrees with that of recent corals, it may be assumed that the anatomy of the soft parts also was similar, and the tetrameral arrange ment, when present, may obviously be referred to a stage when only the first two pairs of Edwardsian mesenteries were present and septa were formed in the intervals between them.
During three years he was experimental assistant to Alfred Donne (1801-1878) in his course of lectures on microscopic anatomy.
The only motion in the air was that of the dripping, microscopic particles of drizzling mist.