W . S. YON STREERUWITZ-GENESIS OF CERTAIN ORE VEINS. 
63 
The other tube had three shorter sprouts, equally knotty and crooked, 
besides a flat string running up 5 centimeters on the glass. 
The first two tubes I set again aside; the two heated ones I put back 
into the water bath and kept them for about fifteen hours at tempera¬ 
tures between 50° and 60° C. After this time the growth in all the tubes 
had reached the surface of the liquid, and there formed considerable de¬ 
posits of gossan. 
The strings in the cool tubes were nearly straight and of uniform thick¬ 
ness from top to bottom, the strings in the heated tubes in their whole 
lengths irregularly bent, unequal in thickness, and of dark color. Two of 
the strings formed pockets of about 6 millimeters diameter, one of the 
pockets sending out two thin strings, the other as many as four. 
These experiments self-evidently removed every doubt about the truth 
of Glauber’s saying, at least as far as the growth of copperas in an alka¬ 
line solution of silica is concerned; though copperas is not exactly a calx 
in the language of alchemists. 
According to experience, quartz must be counted among the best 
gangue matter; and since the peculiar growth in my test tubes, and also 
the artificial gossan, were very similar to certain ore veins and outcrops, 
I inferred therefrom that certain silicious lodes might be the result of 
such growth. I reasoned, though numerous, the existing hypotheses 
leave room for one more—maybe a bridge to some truth, maybe a trail 
leading into a swamp. 
Holding this in view, I went on experimenting with various metal 
salts. Some of them grew more readily than iron; for instance, nitrate 
of cobalt, vanadium chloride; others not at all; others very slowly, for 
instance, sulfate of copper, of nickel, of uranium. Of the last one I 
got, after six months, a few sprouts, about 8 millimeters long and 2 to 3 
millimeters thick. Six months later hardly any changes w r ere percepti¬ 
ble. Most of the ore veins carry more or less iron with the other metals. 
The Cornish miner regards the gossan as one of the best indications, the 
Mexican trusts in his almagres, the South American prospector in his 
pacos and coloraos, and the German in his eisernen Hut. So I added iron 
to the other metal salts, and after a few experiments I had the satisfaction of 
seeing that even refractory growers were carried on bj^ the iron, and many 
of the free growers, if combined with iron, grew more rapidly, forming 
larger or smaller, richer and poorer pockets of the respective metal com¬ 
bination. These pockets sent out veins and veinlets of iron only, or of 
iron and the other metals; all, however, terminated invariably in an iron 
outcrop as soon as they reached the surface of the liquid. 
I also found that most of my oldest veins began to be wrapped up in 
silicious deposits, which, if tli; tubes were kept filled with silicious solu- 
