1 62 Transactions, — Miscellaneous. 



bottom of the bore-hole to above water, the fuse being fastened to it. The 

 cartridge is then complete. Care must be taken that the diameter of the 

 stick and cartridge together do not exceed one inch, else if the hole has not 

 been bored perfectly straight, or if any roughness is left in its sides, the 

 cartridge may not go home, and only the top of the snag will be blown away. 

 The water is sufficient tamping for dynamite. - 



The hole is bored with an inch-and-a-half shell auger, that kind being found 

 superior to American or others, as it cleared itself of the borings better than 

 they did. The hole is bored down to the depth at which it is desu'ed to 

 cut oif the snag. 



The sub-aqueous telescope, or instrument for viewing the snags under water, 

 is indispensable; without it much valuable time would be wasted; it is 

 difficult to see objects clearly imder water even under the favourable circum- 

 stances of a clear sunshiny day and the surface of the river smooth, and it 

 becomes impossible to do so with a slight ripple on it, which is its usual 

 condition. It is necessary to bore into solid wood, some of the snags are 

 rotten at the sides, and a charge exploded there is wasted ; with the telescope 

 you can see exactly where to bore, the amount of dynamite required, and 

 the work can proceed uninterruptedly. 



The charge of dynamite used varied with the size of the snag — from 5oz. 

 to 24oz. were tried ; the average charge was 8oz. It was found to be false 

 economy to use too little, as the explosion then only shattered the stump, 

 and it took double or treble the quantity next shot to clear it away entirely. 

 About half-a-pound was sufficient for a stump two feet in diameter. The 

 workmen judged how many packets of dynamite to place in the hole 

 according to size of the snag, and upon these the cartridge was placed. 

 Though each packet is wrapped in thick paper, they all explode 

 instantaneously. 



The snag which sunk the p.s. " Quickstep" was four feet diameter. The 

 men revenged her by placing one pound and a-half of dynamite in it. 

 After the explosion not a vestige of it could be found. 



Effects of the Explosion, — The action of dynamite on the snags is 

 peculiar ; it invariably cuts them off at the bottom of the auger-hole, leaving 

 a flat surface on the remaining part of the stump, as if a cross-cut saw had 

 done it. One new pile which was desired out of the way, was cut off at the 

 water's edge, then bored as usual, and after the explosion the part from the 

 bottom of the auger-hole upwards floated to the surface with the hole still 

 through it, and bearing signs as if another saw had been at work below 

 water cross-cutting it. The whole of the snags operated ui3on were upright 

 stumps of trees, with one exception. This was a log resting horizontally, 

 out of water. The men hoped to split it up, and bored a hole in the middle 



