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SUMMARY OF CURRENT RESEARCHES RELATING TO 
large photomicrograpbic and projection apparatus of the si me maker, 
bacteriological apparatus from Paris, microtomes of Jung, Microscopes 
of Leitz, and preparations of Tempere andThum. Against the opposite 
■wall of the room were boxes containing numerous photomicrograms by 
Dr. Van Heurck, Thevoz, Muller, &c., and lastly, opposite the Paris 
exhibit came the apparatus from the bacteriological laboratory of 
Wiesnegg. The two shorter sides of the room were occupied by two 
large cases containing Microscopes of Hartnack, apparatus of electrical 
illumination by Trouve, bacteriological apparatus of Rud. Seibert, 
microtomes of Erbe, &c. Above these cases, painted in letters of gold, 
were the names of famous microscopists and celebrated makers. 
In an adjoining room were coloured photomicrograms on glass by 
Lumiere, many photomicrograms of various substances used for purposes 
of adulteration, and a special exhibition by Mdller of type-plates of 
preparations of diatoms. 
The number of exhibitors was comparatively small, but the best 
firms were well represented, and the instruments to be seen were some 
of the finest that have been made. Bacteriology was the weak spot 
in the exhibition. The laboratories of the Belgian, German, and English 
universities sent no contributions, probably in great measure owing to 
the clashing of the Antwerp Exhibition with the bacteriological exhibi- 
tion at the Hygienic Congress in London. 
The various exhibits may be divided into the following sections : — 
(1) Historical exhibition of microscopy. 
(2) Microscopes and their accessories. 
(3) Instruments and apparatus of bacteriology. 
(4) Micrographic preparations, photomicrograms ; and lastly, works 
on microscopy. 
(1) Historical exhibition of Micrography.— Above the cases containing 
this exhibition was placed a portrait of Zaccharias Janssen bearing an 
inscription which stated that the compound Microscope was discovered 
about 1600 by Hans and Zaccharias Janssen. The authentic instrument 
constructed by the Janssens about 1600 formed one of the most inter- 
esting of the objects exhibited. Next to this instrument were four 
authentic Microscopes of Leeuwenhoek. 
Among the compound Microscopes anterior to the 18th century was 
one with four glasses, of the form of the instruments constructed by 
Divini. It was mounted on a tripod, and was formed of two tubes fitting 
into each other, but was not provided with a mirror. Dr. Van Heurck 
exhibited a Microscope by Marshall (London, 1704), which approached 
in its arrangements the Microscopes of to-day ; like them, it has a rapid 
sliding motion and a slow motion effected by a screw. Next to this were 
two Microscopes of Scarlet and Culpepper, which made their appearance 
in England about 1738. In these instruments the body-tube slides in a 
second tube supported on three feet ; the stage is fixed, and the illumi- 
nation is by a mirror movable in all directions, mounted on a foot. 
Several Microscopes of Cuff dating from the middle of the 18th 
century served to show the progress which had been made in Microscope 
construction. They were provided with numerous objectives fitting into 
each other, with micrometer-screw, diaphragm, free stage, mirror and 
lens for the illumination of opaque objects. A Microscope by Brander 
