ANALYSIS OF THE NATROLlTE. 191 



The chronogram of this occurrence is contained in the 

 words* ( ) which fignify " the flame of the 



imperial hghtning;" and give the year (of the Hegera) 1030. 



N. B. The foregoing tranflation (which is nearly Hteral)^ 

 has been made from a manufcript that has been feveral years 

 in my p o fie ffi on ; and which, although without date, bears 

 marks of having been written at a remote period. 



Wivl. KIRKPATRICK. 



V. 



Analyfis of the Natrolite, i?j/ KLAPROXH.f 



JL HE foffil which forms the fubje6l of this analyfis, and to Natrolite found 



which I pive the name of natrolite, for reafons to be Hated '^' ^?S^'*' "^ 

 '■^ buabia. 



hereafter, is found at Hogau in Suabia, on the borders of 

 Switzerland. It is depofited in the crevices, or clefts and ca- 

 vities of the fonorous porphyry. (Klinginftein Porphyr) from 

 having a found, nearly metallic, wliich form the mountains 

 and rocks of Hohentwiel, Hohenkrahen, and Magdeberg. 



The colour of this foffi! is a dirty och-reaceous yellow, ap- Its colour a dirty 

 proaching fometimes to an Ifabella yellow, at other times to^ 

 a vel'ovvith brown, interfeCied with concentric white lines. 

 It !s compaft, its internal fradure has a filky luflre. It breaks its properties* 

 into wedge-like pieces, the edges of which poifafs little tran- 

 parency ; it is not very hard^ extremely brittle, and of=::2,200 

 fpccific gravity. 



' A. 



a. 100 p-rains of natrolite, after having been ignited for Ign'^ed in a 



. *? -, -•, 1 1 a • • 'ri n ' filver crucible, 



fome time in a ^ilvrer crucible, loft nine grains. The figure 



of the ftone v v.« 'etained, but its compadnefs was con- 



fiderably diminifb^d. 



b. Before the blow-pipe on charcoal, natrolite fufes quickly F"^es quickly 



„ « , r- r 11 / /• n • u Lui before the blow- 



into a tranfparent glaf., full of finall air bubbles. pipg^ 



c. Naiioliie placed in a clay crucible, and expofed to the In a porcelain 

 heat of a porcelain rurnace, fufed into a tranfparent glafs of a [^^["^a^^'J'n' 

 light brown colour. glafs> 



* The Perfian oharnfters are given in the Tranfaflions. N. 

 t Abftraft of nn Effay in the memoirs of the Royal Academy 

 ©f Sciences at Berhn, 1803, page 243. 



d. In 



