MINERALS AND GEOLOGY OF CANADA. 15 
Cuemican CHaractEers.*—These, so far as regards the deter- 
mination of mineral species, comprise the results produced by the 
action of acids; and the relative fusibility, &c., of minerals, as 
ascertained by the employment of the blow-pipe. 
«ction of Acids.—The acid-test is resorted to, chiefly for the pur- 
pose of distinguishing the carbonates from other mineral substances. 
The majority of carbonates, as carbonate of lime, carbonate of oxide 
of copper, &c., when touched with a drop of diluted hydrochloric acid 
(the ‘‘ spirit of salt” of the shops), produce a more or less vigorous 
effervescence. This reaction is still more marked, if a small frag- 
ment of the mineral be dropped into a test-tube containing a little 
of the acid. The effervescence arises from the escape of carbonic 
acid. Some carbonates, as carbonate of iron, dissolve very slowly, 
and scarcely produce any effervescence, unless employed in a pulver- 
ised state, or unless the acid be gently heated. Sulphate of lime 
and various other minerals dissolve in hydrochloric acid, but without 
causing effervescence. Quartz, feldspar, &c., on the other hand, 
are quite insoluble. Certain silicates, and more especially those 
named ‘‘ zeolites’? dissolve partially in hot hydrochloric acid, 
leaving the undissolved silica in the form of a gelatinous mass. 
Gold and platinum are not attacked by strong nitric acid, which 
dissolves copper, silver, &c., very readily. Cupreous acid-solutions 
have always a green or blue colour. Red copper ore dissolves with 
effervescence in nitric acid producing a coloured solution ; by which 
characters it may be readily distinguished from the red silver ores. 
* The Chemica] Characters of minerals are discussed in the present paper in the briefest 
terms. To have entered fully into these\characters, would have carried us altogether beyond 
the object in view: the simple determination of the names of Canadian minerals. The 
advanced lectures given daily during the Michaelmas Term in University College, To. 
ronto, by the author, are open to all students desirous of obtaining more ample information 
on the subject. The annexed extract is taken from the authcr’s syllabus to this course of 
lectures: 
“THE CHEMICAL RELATIONS OF MINERALOGY. 
“The Chemical Constitution of Minerals—1, Chemical Nomenclature as applied to 
Mineralogy; 2, The Laws of Combination ; 3, The Atomic Theory: 4, Chemical Notation: 5, 
Construction of Chemical Formule; 6, Isomorphism, or Law of Substitution; 7, Atomic 
Volumes. 
“ The Chemical Examination of Minerals.—i, Action of Acids, &c. 2, Employment of 
the Blow-pipe, comprising: a, Instruments and Appliances; 6. Reagents; c, Operations; d, 
Reactions; and e, Plan of Analysis in the examination of an unknown substance.” 
Students attending these lectures, are strongly advised to go through, also, a course of 
Practical Chemistry, in the Laboratory of University College, under the direction of Profeg- 
sor Croft. 
