[265] Tachenii Hippocraticæ Medicinæ Clavis, p. 236. 1669.

[266] Collectanea Chymica Leydensia, edidit Morley. Lugd. Bat. 1684, 4to, p. 97.

[267] For an account of various kinds of secret writing see Halle, Magie oder Zauberkräfte der Natur. Berlin, 1783, 8vo, v. i. p. 138.

[268] Hist. et Mém. de l’Acad. des Sciences à Paris, 1737, pp. 101 and 228.

[269] Historia Cadmiæ fossilis, sive Cobalti. Berl. 1744.

[270] This account, together with Teichmeyer’s receipt for preparing it, may be found in Commercium Litterarium Norimbergense, 1737, p. 91.

[271] “Copiosius minera bismuthi tam ab aqua forti quam ab aqua regia dissolvitur, restante pulvere albo corroso; solutio in aqua forti roseum colorem sistit, quæ si sali in aqua soluto, secundum præscriptum D. J. W. in clave, affundatur, abstrahatur, ex residuo extrahitur sal roseum, quod pulverisari et cum spiritu vini extrahi potest: adeoque hæc autrix jam anno 1705 publice totum processum et fundamentum sic dicti atramenti sympathetici, quod a calore viridescit, evulgavit.”—Pot, Observ. Chym. collectio prima. Berolini, 1739, p. 163.

[272] So thinks Gesner in Selecta Physico-œconomica, or Sammlung von allerhand zur Naturgeschichte gehörigen Begebenheiten. Stutgard, vii. p. 22.

[273]

[Inks formed of solutions
of the following salts,		and washed with
solutions of		become
Muriate of antimony,tincture of galls,yellow.
Green vitriol,tincture of galls,black.
Nitrate of cobalt,oxalic acid,blue.
Subacetate of lead,hydriodic acid,yellow.
Arseniate of potash,nitrate of copper,green.
Nitrate of copper,prussiate of potash,brown.
Solution of gold,muriate of tin,purple.
Perchloride of mercury,hydrochlorate of tin,black.]