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detonating cap, is then lowered down the hole until it touches the charge. Generally, 
the hole is then tilled with water, and fired by a lighted candle “ snuff’” being placed 
under the fuse which projects from the hole. If the hole has been drilled in an upper 
or horizontal direction, clay or sand is used for keeping the charge and fuse in their 
proper positions. For blasting with gunpowder, the charge, whether loose or in 
cartridge form, is placed in the hole with the fuse and firmly packed; then the process 
of tamping pounded clay slate, free from grit, with a copper bar and hammer, is carried 
on until the hole above the charge is strongly tamped up; the fuse is then fired 
similarly to other blasts. With this method of charging, there is increased danger to 
the miner, in addition to the loss of time. 
Mr. Inspector Grainger (Sandhurst) writes—“For charging powder 
I the ordinary scraper and spoon are used. A few of Veale and Thomas’ 
‘ chargers ’ are employed, but they do not seem to come into general use, 
although I consider they are by fin- the best. They can be made to any 
size to suit. I witnessed several trials of them and was well satisfied. I 
have no hesitation in stating that they are a great improvement on previous 
modes of charging, and especially as regards their safety.” 
I give here a sketch of the apparatus, the invention of Messrs. Yeale 
and Thomas, California Gully, Sandhurst, and a description of which is as 
follows:—“ It consists of a copper tube, to fit into the hole to be bored, 
and inside this tube is fitted a copper piston, or ‘ramrod,’ if it might be so 
called. The powder is placed in one end, which is then inserted in the 
hole, and the powder forced out of the tube into the hole. In a downward 
hole the tube can be put into the bottom, and the powder poured down. In 
the first place, there is a great saving of time as compared with the use of 
the 4 spoon’ and ‘scraper,’ and, secondly, the liability to accident is much 
less. There is no fear of ignition from friction in the use of copper, and 
I the tube going right to the end of the hole, the bar does not touch the sides 
of the hole, and therefore a frequent cause of accident is removed. At a 
trial of the ‘ charger ’ made at Sandhurst, the idea was regarded as an 
— excellent one, and the miners agreed that it would save time and make the 
work much safer. There was some doubt whether an ‘upper’ hole could be charged, 
but the patentees, who were present, gave an assurance that this could be easily and 
effectively done. The cost of the chargers is said to be only 30s. each.” 
On the subject of charging and blasting, I make the following extracts from 
British Mining :— 
Holes bored by machine drills cannot be placed in accordance with the line of least resistance. To 
compensate in somo degree for this defect, incident to machine work, the strength of the charges should be 
varied according to the resistance which they will be required to overcome. The holes for nnkoying the 
face will require the heaviest charge of explosive material, since the conditions for getting out the cut or 
wedge are usually most unfavorable for the power of the explosive. The quantity of explosive for each 
hole must vary greatly, since it will be dependent on the nature of the rock and the resistance offered to the 
blast. The proper charge can only be ascertained by experience. If holes are fired singly, more dynamite 
will be required than if fired simultaneously. For taking out the wedge or centre-cut, the strongest 
dynamite should be used. For enlarging the face round the wedge or centre-cut, No. 2 or 70 per cent, 
nitro-glycerine dynamite will often prove strong enough. In schist and sandstone rocks of a bedded 
character good results have been obtained by the use of cartridges of compressed powder being ignited at 
the bottom. At Roucluimp, in France, dynamite and powder exploded together gave excellent results. It 
was held that powder prolonged, as it were, the time of the explosion, and exerted its force on the rock 
weakened by the quicker-rending streugth of the dynamite.At St. Gothard, very deep holes 
were tried; but in many instances it was found that “sockets” were left after the holes were blasted. By 
giving the holes a greater diameter, this drawback was materially abated. As, however, the consumption 
of dynamite was found to bo large, it was afterwards used surrounding a cylinder of clay. In this way the 
weight of the explosive was said to be sensibly lessened without decreasing to a proportionate extent the 
measure of the result. To obtain a maximum effect from the detonation of dynamite, it should be placed 
at the bottom of the shot-hole and confined by water, or otherwise gently tamped with about three inches of 
soft clay. Many miners assert that tamping is unnecessary. The fact is it is not so essential a matter 
with quick-rending explosives A s with black powder. In the one case the liberation of the expansive gases 
is instantaneous, in the other it is gradual; but with any explosive the complete confinement of gases must 
increase the effect. The filling up of any space round the charge is also important .If water 
be employed for tamping purposes, the detonators attached to the fuse should be protected, so that no water 
can enter between the fuse and the detonator to interrupt the igniting operation. Even if the fulminate 
should become damp, this circumstance alone will materially lessen the power of the fulminate, and, perchance, 
cause the dynamite to burn, losing thereby its money value, as well as its disrupting effect. The order of firing 
the shot-holes should be determined at the time of charging and tamping them. Naturally such holes should 
be selected as will rupture and unkey the rock to the desired depth, and which will also secure the most 
