274 Fig, 243:
include the usual selection for the time, e.g. insects, plants, seeds, hairs. There are
eighty-four cells containing opaque objects that have to be viewed by light incident
from above. The sliders and cells are numbered in ink. The booklet lists, in addition to
the above, twenty-four specimens specifically for the solar microscope, and these seem
to be missing.
Abraham Ypelaar (1736—1811) was a preparer of microscopic specimens of very
great repute. The quality of his production is apparent in this collection,nd in the
cabinet described under Cat. 274. Other examples of his work exist in the Rijks-
museum voor de Geschiedenis der Natuurwetenschappen at Leyden.
Rooseboom (1940a); see also Cat. 274
274 CABINET OF MICROSCOPE SLIDES 1790 (365/3I' Fig, 243
Sliders English; cells by Abraham Ypelaar, Amsterdam
Cabinet 273 x 150 x 178; sliders 115 x 18, cells of diameters 20, 16, 12.
Mahogany cabinet with twelve drawers, four of sliders showing thin sectionssjthree of
cells with transparent objects, one of cells with opaque objects, and four empty.
The forty-two ivory sliders are numbered in two series from 1 to 21. The second series,
has had additional numbers pencilled in, running from 23 to 43, thus omitting no. 22.
An accompanying list, handwritten in English, names the specimens, which are
sections of wood, plant roots and stems, held between mica disks, and has number^'
added for the second series that also omits no. 22.
In July, 1790, Van Marum noted that he had bought in London forty-two sliders,
containing 168 microscopic objects for £ 5-5-® (MV).
Forty-two cells, diameter 20, made of ivory with glass disks held in place by split
brass rings, contain transparent objects. Each cell is numbered and named in ink, e.g.
‘T Antipathes paniculata” . On a single sheet of paper, handwritten in pencil by a
Dutchman, is a list of the specimens with notes.
Another group of 144 cells, diameter 12,’and numbered in pencil, contain transparent
objects, including many different fleas, lice, hairs, fish scales, skin etc., and a further
forty, diameter 16, contain opaque objects, including insects, feathers, small shells, etc.
A booklet contains a list of the specimens handwritten in Dutch, in three groups, tha%'
of 144 and forty described above, and another of thirty-six comprising marine vegetation.
It may be that these latter are included among the forty-two largest cells, but no
correlation has been made.
The Inventory records that É, chest of microscopic objects contains wood sections
prepared in London, the rest being by Ypelaar. The order was given to Ypelaar on
24 June, 1790, which was for 200 zoological microscopic objects according to a given
list, at a price of ƒ1 each, except for thirty-six objects of marine life for which the price
was f 2 (MVHAt these prices, the 200 objects would have cost f 238, and the cabinet
itself would have been extra. Payment was made to Ypelaar in 1791 for ƒ 276.
Another set of microscopic objects that were once in the collection and that are now
not identifiable, or lost, is mentioned in a letter of 10 October, 1790, from Cavallo to
Van Marum. Cavallo had bought, for £ 1-18-0 at an auction, “ a set of long wooden
sliders in a proper case, which altogether contain 37 large objects for the microscope
among which are 8 slices of wood as fine as those which you had, and really beautiful;
by comparing them with the catalogue of your collection, they are all different except
one” . These slides were offered to Van Marum, who accepted them, and they were
despatched on 2 November 1790. See also Cat. 273.
Int'. 60mH
275 MICROSCOPE SLIDES % 18th C. (365/1) Fig. 244
Set of six bone sliders (66 x 12) in a pasteboard case covered with black fishskin. Each
slider has four specimens held between disks of mica located by split rings of brass. A
sheet qf paper lists, in English, the objects contained in five sliders, the sixth being “ a
spare slider to be fill’d at pleasure” . A translation into Dutch has been made onto the
reverse of the sheet. The objects include: the down of a butterfly’s wing, a human hair,
the Scale of a perch, human skin, a piece of cork, a crab louse.
This set of slides probably belongs to the solar microscope supplied by Jan Paauw,
see Cat. 268.
276 MICROSCOPE SLIDES H 1789 (365/2) Fig. 244
Set of eight ivory sliders (107 x 18), each to hold four specimens. A booklet, written in
English, lists the objects. Also listed in this booklet are sixteen slides holding opaque
objects, and these are probably the ones with the lucernal microscope supplied by
George Adams, see Cat. 269.
277 MICROSCOPE SLIDES % 18th C. (nil) Fig. 244
Set of four ebony sliders (83 x 15), each holding four specimens for transmitted light.
There is no box or list, and their source cannot be identified.