H4 
Scientific Notes. [January, 
to avoid removing any paper or size from beneath. This task of scraping 
was easy enough, for the leather was reduced to the consistency of Scotch 
snuff. On analysis of the watery extradl of this leather the following figures 
were obtained : — 
Free sulphuric acid in decayed leather.. .. 6*21 p.c. 
Combined ,, ,, ,, .... 2*21 ,, 
Total ,, ,, ,, .. >• 8*42 ,, 
Writing of rare minerals found in Colorado, Mr. T. F. Van Wagenen, in the 
“Engineering and Mining Journal,” says that thallium, indium, and cadmium 
have lately been detected in ores from that state. Of the rarer metals 
there have been found in Colorado, besides the three mentioned above, nickel, 
cobalt, selenium, tellurium, uranium, bismuth, molybdenum, and platinum, 
and there is scarcely a doubt that columbium, thorium, titanium, and 
vanadium will be recognised as soon as proper search is made. A belt of 
telluretted veins is believed to traverse the entire state from north to south. 
Two yeais ago sylvanite and alaite were found in San Juan county. The 
principal locality for bismuth ores is in Geneva, where two mines are being 
worked that carry a considerable quantity of schirmerite. Sulphide and car- 
bonate of bismuth occur on Sugar-loaf Mountain, Boulder county. Nuggets 
of native bismuth are common in the upper gulches of the Blue Valley; the 
same metal has been found also in the Arkansas Valley. Nickel ore, ranging 
from 2 to 5 per cent, has been found in three localities. Among the minera- 
logical curiosities of the tellurium belt may be mentioned a telluride of 
mercury found in the Mountain Lion Mine. Native mercury and amalgams 
of both gold and silver have also been found at several points along this belt. 
We are likely soon to hear of columbium-plating, a metal which is very 
much like nickel, but whiter, like tin. It was first found, more than fifty 
years ago, in the United States, near Middletown, Conn., and named in 
honour of America. It was thus far very scarce, but has now been found at 
Marion, N.C., and also in the Amazon stone of Colorado. If it becomes 
abundant enough to be used in the arts we may soon have a valuable addition 
to the useful metals, and also to their compounds or salts. The metal forms 
an acid like tin, called columbic acid ; tin forms stannic acid, and the com- 
pounds of this acid with bases are stannates, very useful in the arts ; the 
compounds of columbic acid with bases must be called columbates. They 
have not yet been investigated, but will likely be found extremely useful for 
some purposes. 
As a means of preventing the explosion of fire-damp in coal mines M. Basin 
recommends ventilation with compressed air, watering the galleries (in dry 
mines), and the use of Bastie’s toughened glass instead of wire-gauze for the 
cylinders of safety lamps. The tube which gives vent to the products of com- 
bustion will contain several superimposed layers of gauze. 
From the “Mineral Statistics of Victoria for the Year 1876” we learn that 
the total yield of gold for that year in this colony has been 357,901 ozs. from 
alluvial sources, and 605,859 ozs. from quartz rock. The total yield of silver 
was 26,356 ozs., the greater portion of which was parted from gold smelted 
at the Mint. The exports of tin were 34 tons 9 cwts. During the year 
2529 tons of antimony ore were raised, and 606 tons of ore, 474 tons of 
regulus, and 254 tons of crude antimony were exported. 
