398 
POPULAR SCIENCE REVIEW. 
added, to which three eye-pieces and three object-glasses are attached, in 
such a manner that no labour is lost in setting up the instrument, or in making 
the necessary changes. A binocular body, with the necessary draw-tubes, may 
also be added, readily adjustible with little practice ; and, finally, a stage with 
actions, so that the instrument only needs polarizing apparatus, parobolic 
reflector, lieberkulm, camera lucida, and micrometer, to make it equal to doing 
any work which the microscopist may be called upon to perform. In these 
days of elegance and design, it may be objected that the microscope which 
possesses these advantages is not so symmetrical as higher-priced ones, but 
we doubt not that the beauty and completeness of the workmanship will 
amply compensate for any imaginary deficiencies on that score. 
MINERALOGY AND METALLURGY. 
Mineral Produce of Italy. — The following valuable information, relative 
to the mineral produce of Italy, is derived from a report by the commis- 
sioners of jurors of the Exposition at Florence : — 
Sulphur. — The annual produce of the sulphur mines of Italy is estimated 
at 300,000 tons, valued at thirty millions of francs. Sicily produces the 
greatest quantity, while the Romagna produces 8,000 tons. 
Iron. — 35,000 tons are produced each year. This is all charcoal iron of 
fine quality. 
Lead. — The produce of lead is 7,000 tons. The island of Sardinia alone 
furnishes 17,000 tons of lead ore (Galena). 
Copper. —Annual produce, 1,500 tons, obtained from the mines of 
Monte-Catini and Capanne-Vecchi, in Tuscany, Agordo, in Venetia, and 
the Vale d’ Aosta. 
Boracic Acid. — Two millions of kilogrammes (rather more than two 
pounds avoirdupois) are produced in Pisa. The works of Count Lar- 
derele yield 1,800,000 of these. 
Combustibles. — The lignites (wood coal) produced do not exceed 60,000 
tons per annum. They have no coal in Italy but the poor anthracite of 
the Alps. 
Nickel. — The nickeliferous pyrites of the Alps yield 50,000 kilogrammes 
of metallic nickel annually. 
Gold. — These pyrites (nickeliferous) also yield, by amalgamation, 
500,000 francs in gold per annum. 
Mercury. — Tuscany produces 3,500 kilogrammes. 
Manganese. — 1,000 tons a year are produced from the mines of St. 
Marcel and Frammura. 
Antimony. — Tuscany produces more than 50 tons of antimony per 
annum. 
The Aqueous Origin of Granite. — It is well known that Mr. Sorby, of 
Sheffield, some years since, called attention to the fact, that the quartz 
crystals in granite had hollow cavities which contained water; Mr. 
Alexander Bryson has been pursuing this inquiry, the whole of which 
tends to support this view. In a paper recently published, Mr; Bryson 
states his conclusions thus : — 
