de faire quelques nouveaux reglements utiles, que le nou- 
veau president trouve tout etabli quand il y viendra. Ce 
sera autant de gagne. J’ai devant moi un ouvrage Ir&s- 
important de Mr, Aepinus, professeur ä Petersbourg, dans 
lequel il donne une theorie presque tout-ä-fail salisfaisante 
de l’electricit@ et du magnelisme. 
CXXXVI J.6G. Zimmermanm, Brugg, 18. Dec. 
1760: L’epoque du nouvel an me rappellera ce que vous 
avez fait pour moi il ya un an. De ma vie je n’oublierai 
a quel point vous m’avez rendu content et heureux, en 
sentant et tachant si genereusement de remedier aux desa- 
grements de ma situation. Dieu vous rende le centuple. 
CXXXVI. Valltravers, Siockholm, 13. Januar 
1761: 1 have received great Instructions from Mr. Schwabe, 
President to the swedish Royal Academy of sciences and 
Councellour in the College of Mines, a Gentleman, who has 
seen and observed the best Salt-Pitts in Europe, and who 
knows a great Deal in those !hings, as well as other Mi- 
nerals. He has instructed me, how to find out any Stra- 
tum of Salt Rock, by the Brines, the red Plaster, and the 
Plant Kali geniculatum or Salicornia, the three most infal- 
lible Index’s; he shew’d me how to proceed in fracing a 
Salt-brine sidewards up to the Salt Rock, without loosing, 
or weakening the Brine, by never quitting the upper part 
of the Stratum of Clay, thro’ which all Salt-Brines gene- 
rally flow, and by following its enclined Plane upwards; 
since all fluids must move downwards. He communicated 
also to me his Drawings of several Salt-Pans and gave me 
his judieious @conomical observalions upon Ihe same. 
CXXXVIN. Beylon!'3), Stockholm, 16. Januar 1761: 
13) Ein Waadtländer, Vorleser der Königin Ulrike Luise von 
Schweden, welche sich sehr für die Wissenschaften interessirle, 
