The 1875 Remembrance
In 1875 seven Leeuwenhoek microscopes (three silver and four brass) were exhibited at the Leeuwenhoek exposition in Delft celebrating the 200th anniversary of his discovery of microrganisms. Harting's Gedenkboek reproduced the Lijst der tentoongestelde voorwerpen (list of exhibited objects); the microscopes are on pp. 126-127, items number 55, 56, 60, 61, and 62.
- Numbers 55 and 56 were silver microscopes loaned to the exhibition by Prof. J. A. Boogaard, Director of the Anatomish Kabinet of the Leiden Hoogeschool, and by Ds. J. N. Scheltema, Director of the Stedelijk Museum, Gouda. Number 55 has gone missing and number 56 is the 80x silver on the right sidebar.
- Numbers 60 to 62 included a brass microscope, noted as having a magnification of 270 times. It was loaned by Prof. P. Harting of the Zootomisch Laboratorium of the Museum of Natuurlijke Historie in Utrecht. It would be the 266x brass microscope on the left sidebar.
- Number 61 had three brass microscopes, two with zeer kleine lenzen (extremely small lenses), loaned by the Haaxman family. They would be the 118x, 74x, and no lens brass microscopes on the left sidebar.
- Number 62 was noted as having a specimen between two dekglazen (cover slips?). It was loaned by R. T. Maitland, Director of the Royal Zoological and Botanical Garden in The Hague. It is the 68x silver on the right sidebar.
Items number 57, 58, and 59 are also associated with Leeuwenhoek. They were loaned by Prof. P. L. Rijke, director of the Physisch Kavinet of the Leiden Hoogeschool. The text reads (my translation):
57. A brass microscope apparatus for observing the circulation of blood in animals (on right; click to enlarge). This apparatus consists of one rectangular copper plate bent at both ends, in whose bent-over portions are arranged round openings, intended to hold a glass tube, which is then clamped by springs.
Water and a small fish are enclosed in this glass tube, with the fins of the tail placed so that one can observe the blood circulating. The lens enclosed between two plates is set in front of the tube, by means of a perpendicular plate. The Catalogus of the sale of his microscopes mentioned that he had constructed eight silver and four brass apparatuses. Leeuwenhoek was the first who had constructed that a similar tool of that kind, intended for the described purpose.
(On this apparatus is, however, on the screw side, a mark hammered in and under it Stadswapen van Leiden (Leiden city seal). This supposes that the described object is a legacy of Leeuwenhoek's invention and improvement through the device provided for in order to bring the lens closer to or farther from the opening, for use in the glass tube. (Perhaps the device so modified was from the hand of Musschenbroek?).
58. A red morocco leather home-made little case, on which is his own hand is written Anth. van Leeuwenhoek. Herein were, in compartments sewn closed, five lenses mounted between very thin brass plates, intended to be placed in front of the above-described tube.
59. A ground lens, not yet set in brass. This lens was wrapped in paper and was placed in the sixth compartment of the moroccan case. (It was to improve the view between two watch glasses).
Then, three brass microscopes were still in the Haaxman family, two of which were eventually bought by the forerunner of Museum Boerhaave in Leiden. Today, one of those microscopes is still preserved by a descendant of the Haaxman family.
