Plate X V I . T h e constellation ‘H o ro lo g ium ’ from A d am s ’ Celestial G lo b e (C a t. 93)-
M I S C E L L A N E O U S
342 CRYSTAL MODELS: delTsle 1785 (nil) Fig. 303
Size about 20-30.
This is a set of models made of baked clay showing crystal forms after the scheme
published by Jean Baptiste Louis Rome de l’lsle (1736-1790). On each model is a
paper label printed with the group number and the number within that group in
accordance with the scheme of Rome de l’lsle. There are seven groups originally
comprising 444 models, of which some are now missing; they are as follows:-
Group Original number Missing
I 40 2
II 40
III 106 5
IV 128 14
V 43 3
VI 46 3
VII 41 9
Total 444 55
Van Marum was introduced to Rome de l’lsle during his visit to Paris in July, 1785,
and acquired a set of crystal models. According to the invoices, he paid 55 louis d’or.
Van Marum mentions these models in a letter of 9 December, 1799, to R. J. Haiiy.
Rome de TIsle (1772) ; (1783) especially iv, illustrating all the forms. For further
references, see Cat. 343.
342
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»
Fig. 303
343 Fig. 304
Both the above figures are to the same scale.