THE EXHIBITION OP 1862. 
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studied. Tims the forms adapted for marble fail in granite. 
The granite manufactures, chiefly from Aberdeen and Cornwall, 
are beautiful in quality, but small in number and variety. 
Of constructive materials, slates are the most remarkable. 
The exhibition of them in 1862 is far superior to that in 1851. 
Probably no such collection as that now made was ever brought 
together, and certainly none could be obtained out of England. 
These objects are not perhaps attractive ; but they astonish by 
their size, and by the perfection of the cleavage, admitting the 
preparation of long, hard, firm slates, a sixteenth of an inch only 
in thickness, and of slabs, without a single flaw, two hundred 
square feet in area. The continental slates are very poor com- 
pared with these. 
One word here with regard to the imitative marbles, enam- 
elled on slate, by Mr. Magnus. It is impossible to praise too 
highly the progress made by this manufacturer since 1851. 
He has attained so near to perfection, that it is difficult to 
imagine what will be his next improvement. These imitations 
seem especially adapted for house decoration, owing to their 
extreme hardness and moderate cost. 
We have little space left to notice the remaining objects 
exhibited in this large and important class. China and pottery 
clays, fire-clays, and sands, do not change, and show no pro- 
gress. Mica and steatite, and some other minerals exhibited, 
are equally stationary. There are a few educational collections 
in the building, but these also offer little worthy of notice ; and 
the same remark may be made concerning the cements and 
artificial stones. 
One word of comparative remark in regard to the different 
countries. Except Australia, no country has shown a great 
stride in advance of the last Exhibition in its mineral produce. 
England, Wales, and Scotland, have sent less, and what is sent 
is on the whole of smaller interest, than before. Ireland has 
hardly sent anything. France has done little, and not better 
than before. Belgium has done well, and the Zollverein admi- 
rably. Austria, on the whole, is good, but justice has hardly 
been done to its collections. Canada, and the other British 
provinces of North America, are respectable, and even good. 
Spain is slovenly, and Portugal little better. Russia decidedly 
good. Sweden, Norway, and Denmark, not remarkable. 
Brazil is good. 
Thus, in a few words, we have endeavoured to sum up the 
impression made by a study of the minerals of the Great 
Exhibition of 1862. We doubt exceedingly whether another 
such exhibition, conducted in the same manner, would be in 
any sense desirable at the end of another decennial period ; for 
the means of instituting a comparison are so very few, and 
