[19] Cimelium Geographicum Tripartitum. Dresden, 1680.
[20] Kunstgeschichte von Augsburg, p. 167.
[21] Gemmarum et Lapidum Historia. Lugd. Bat. 1647, 8vo, p. 468.
[22] Magnes, sive De arte magnetica. Coloniæ, 1643, 4to, p. 221.
[23] Boot. Hist. Gemmarum, p. 473.
[24] This machine was used by Sulzer during his tour. See his Journal, published at Leipsic, 1780, 8vo, p. 3. It has been since improved by Schumacher, a clergyman at Elbing, by Klindworth, Catel at Berlin, and by an anonymous clergyman in the Schwabisches Magazin, 1777, p. 306.
[25] This model is preserved in the collection of the Academy.
[26] There is a figure of it in the Penny Cyclopædia, vol. xvii. p. 367.