ROCK BLASTING.

ROCK BLASTING.

A
PRACTICAL TREATISE
ON THE
MEANS EMPLOYED IN BLASTING ROCKS
FOR INDUSTRIAL PURPOSES.

BY
GEO. G. ANDRÉ, F.G.S., Assoc. Inst. C.E.,
MINING CIVIL ENGINEER; MEMBER OF THE SOCIETY OF ENGINEERS.

LONDON:
E. & F. N. SPON, 46, CHARING CROSS.
NEW YORK:
446, BROOME STREET.
1878.

[v]

PREFACE.

During the past decade, numerous and great changeshave taken place in the system followed and themethods adopted for blasting rocks in industrialoperations. The introduction of the machine drillled naturally to these important changes. Thesystem which was suitable to the operations carriedon by hand was inefficient under the requirementsof machine labour, and the methods which had beenadopted as the most appropriate in the former casewere found to be more or less unsuitable in thelatter. Moreover, the conditions involved in machineboring are such as render necessary stronger explosiveagents than the common gunpowder hithertoin use, and a more expeditious and effective meansof firing them than that afforded by the ordinaryfuse. These stronger agents have been found inthe nitro-cotton and the nitro-glycerine compounds,and in the ordinary black powder improved in constitution[vi]and fired by detonation; and this moreexpeditious and effective means of firing has beendiscovered in the convenient application of electricity.Hence it is that the changes mentionedhave been brought about, and hence, also, has arisena need for a work like the present, in which thesubjects are treated of in detail under the newaspects due to the altered conditions.

GEO. G. ANDRÉ.

[vii]

CONTENTS.