Hunt.—Notes on blowing up Snags in the Waikato River with Dynamite. 161 
Art. XII.—Notes on blowing up Snags in the Waikato River with Dynamite. 
By R. R. Hon. 
Plate III. 
[Read before the Auckland Institute, 22nd October, 1877.] 
Tue channels through the pumice sand in the “ sunken forest" near 
Rangiriri, Waikato river, are constantly shifting and thus often expose new 
“snags ” or the remains of trees, which are very dangerous to steamers and 
barges plying on the river ; as a proof of which may be mentioned the fact, 
that three steamers and many barges of the Waikato Steam Navigation 
Company have been snagged and sunk by them ; this company (of which 
the writer is manager) whenever dangerous snags appear, blows them out 
with dynamite, and a few remarks on their experience may not prove 
uninteresting. 
First selecting a snag to be removed, a boat is moored above stream of 
it and athwart the current, by anchors, bow and stern; these steady her 
in a breeze, and by their help the boat can be pulled up stream when the 
fuse is fired, and after the explosion she can by them be dropped back into 
exactly the same position as she had previously occupied; this being 
important as it sometimes happens that a second shot is required, and no 
one who has not tried can imagine how difficult it is to find the same snag 
or spot in running water after you have left it unmarked. 
Now, supposing the boat to be in position, the next thing to be done is 
to carefully view the snag with a sub-aqueous telescope (if it may be so 
named) made as per sketch (Plate III.). 
A hole is then bored down the stump with an inch-and-a-half auger to 
three feet six inches below low summer level, that depth permitting the 
steamers to pass over safely. 
Some dynamite and a cartridge previously prepared are then placed in 
the hole, the fuse fired, and the boat hauled away about fifty feet, a perfectly 
safe distance; soon the explosion is heard, and then, usually, the snag is a 
thing of the past. All this seems simple, but it is easier talked of than 
done. 
The cartridge is made up watertight simply to prevent the cap getting 
wet, water does not injure dynamite in theleast. The sketch will show the 
fuse (that coated with rubber is the best) inserted in the cap, which is about 
an inch long, the cap is buried in the ignition charge, this being a particular 
kind of dynamite, the charge is connected with one of the ordinary 2}0z. 
packets of dynamite, these are then wrapped in common calico, tied tightly 
with string, and dipped into melted tallow or pitch to render the whole water- 
proof; attach this cartridge to a slight stick, long enough to reach from the 
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