aa ee ee ee ee aS ee ee a eae ee ee ae, eee 
2 q res a salad _= 7 = 
On the Artificial Formation of Minerals. 293 
‘whose origin, it is very probable, intense heat has exercised 
an essential influence, which have never been produced arti- 
ficially, nor observed in the products of metallurgical opera- 
‘tions. The very happy, and in some respects fertile, idea of 
Ebelmen to expose substances to the joint influence of heat 
‘and a solvent capable of being volatilized, and thus to obtain 
them crystallized, has furnished some very valuable results ; 
‘but, although boracic acid—the solvent used—has been found 
in many native minerals, in which its presence had not been 
suspected, still its occurrence is too rare to admit of the 
opinion that it has played any very considerable part in the 
production of the more widely distributed minerals constitut- 
ing the earth’s surface.* 
Forchhammer has recently made experiments of the same 
character as those of Ebelmen, but with substances, as sol- 
vents, which are less rare than boracic acid—chloride of so- 
dium, calcium, magnesium, &c. 
The production of apatite was the object of his s first experi- 
ments ; and he was led to them by the results of his analyses 
of sea water, and his observations of the constant presence in 
it of phosphate of lime, together with a still smaller amount 
-of fluoride of calcium. 
After failing in every attempt to produce apatite in the 
wet way, and guided by the circumstance that apatite occurs 
chiefly in lava, dolerite, granite, and metamorphic rocks, 
under conditions which appear to indicate.an igneous origin, 
-he came to the conclusion that if this was the case, chloride 
of sodium might have been concerned in its formation. 
‘By melting phosphate of lime with chloride of sodium, and 
_ allowing the mixture to cool very slowly, a mass was ob- 
_ tained which presented a great number of cavities containing 
an abundance of long columnar crystals. The residue left, 
after treating this mass with water and then with acetic acid, 
consisted of — 
Lime, “ Bb uy; 5°80 
Hydrochloric wisi nee tes 5°61 
Phosphate of lime, a + 88-07 
Oxide of iron, aA cok a Lace * 
* Ueber die Einwirkung des Kochsalzes bei der Bildung der Mineralien 
Ee * Annalen der Physik und Chemie, 1854, No. 4. 
