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would be impossible. The transport, however, might easily be 
rendered much safer, by forbidding gunpowder-carts to pass 
along the streets except during a few hours in the morning, 
allowing only covered vans to be used, and fixing certain inter- 
vals within which no van should approach another. Finally, 
powder should never be packed in the light kegs used by some 
manufacturers, which are continually liable to leak, for loose 
powder is always exposed to ignition by any one of a hundred 
accidents. There are cases recorded of explosions having taken 
place through powder leaking from a tumbril, and forming a 
train upon the ground, which was fired by a spark struck from 
the shoes of one of the horses drawing it. Good strong barrels 
should always be used, and they could of course be returned 
when empty. 
After the Eegent’s Park explosion there were some fears 
expressed as to a possible explosion at Purfleet, where about 
50.000 barrels of gunpowder are stored in five large magazines. 
If five tons on board the canal-barge could do so much damage, 
what, it was asked, would be the effect of an explosion of the 
2.000 tons at Purfleet ? Attempts were made to calculate the 
radius of destruction by Mallet’s formula for the effect of burst- 
ing shells — the fact being disregarded that the bursting of a 
shell and the blowing up of a magazine are essentially different 
affairs. We were told how all East London would suffer from 
the shock, how several villages in Kent and Essex would be 
destroyed, and how trains would be thrown off the railway-lines, 
gasometers wrecked, and a wide district plunged into darkness. 
We must not forget that an explosion in the open country 
would have relatively much less force than an explosion in the 
midst of closely-built streets like those about Eegent’s Park. 
An explosion at Purfleet would be very terrible, but probably 
not half so destructive as one might expect at first sight.* 
Then the Government must keep this large store of powder 
somewhere ; 50,000 barrels could not be manufactured on an 
emergency, and Purfleet offers advantages in the way of safe 
and easy transport from Waltham, and shipment to India and 
the Colonies, which mark it as a good site for our chief maga- 
zines. The gunpowder might indeed be distributed in nume- 
rous magazines, at various points along the lower part of the 
Thames, but this would really be to increase the chances of an 
explosion ; for the more numerous is the staff of superintendents 
* The explosion of a large magazine is really the successive explosion of 
various portions of its contents, not the detonation of the whole mass. 
This is why it is fallacious to attempt to estimate the effect of the explosion 
of 2,000 tons by comparing it with the explosion of a large shell, or of a few 
barrels on board a barge. 
