THERMALLY scattered light emitted from nominally very pure single crystals of sodium chloride is directly seen in ultramicroscopic examination of impurity centres 1,2 using illumination at right ...

IT appears to me that the fundamental significance (apart from its medical importance) of Mr. J. E. Barnard's1 observations on the ultramicroscopic organisms known as filterable viruses has not ...

Microscopy by ZsigmondyIMPORTANT DISCOVERY MADE IN FIELD OF MICROSCOPY; Two German Professors Invent New Method of Observation Whereby Particles Which Hitherto Have Been Ultramicroscopic Are Made ...

Bacteriologists do not know whether an ultramicroscopic germ causes that disease or whether an ultramicroscopic virus (which may be a living organism or an active chemical entity) is involved.