Ri
88
Sample 4941
It therefore appeared that the drun had been "burnt" by an eleotrical short-circuit from a rubber-insulated wire. Only one outside the building could have caused this, and this was the heavy
wire electric cable running along the outside wall, already referred to, and of which a piece was found down on the pavement. The portion of this wire crossing above the hole in the wall showed no signs of short-cir- cuiting; it was therefore conjectured that the drum had passed this wire safely.
From this it was reasoned that the drum had been short-cir- cuited and burnt within the godown; this would of course provide the origin of the fire.
The technical staff of the Hong Kong Electric Co. Ltd. exam- ined the installation and carried out tests, at which Insp. Shaw and I were prosent. It appeared that the fuses of the godown installation had "blown" and would "blow" at 30 amps current, whereas more than twice this current would be required to burn the hole found in the drum.
Insp. Shaw further pointed out that the drum might have been blown out only on to the pavement, where one end of the electric cable had afterwards descended on it and caused the hole.
(b)
This theory was therefore abandoned.
Theory of ignition by material descending the fluc-pipe.
On 30 Sep. 48, as we were examining the material of Stack 38 (Plan No. 1), Insp. Shaw noticed a small hole in the ceiling above, of which the position is shewn on the plan. This was found to lead to a flue passing through the upstairs flats to the roof, and was evidently a relic of the original intention, that the ground floor or the building should be occupied by shops.
On the floor of the godown under the hole were fragments of a Chinese stove or "chatty". The flue pipo appeared to have run downwards to godown ceiling level, where it had originally been blocked by a thin covering of cement floated over the hole. Two side holes or entrances to this pipe wore discovered in the upstairs flats.
Water was poured through the pipe from first floor level in order to discover whence it led, and a great quantity of soot and mis- oellaneous rubbish descended; this appeared to have been blocking the pipc.
It was therefore concluded that the fire had cracked away the cement and exposed the hole, allowing some of the accumulated rub- bish in the pipe-end to fall; the theory was accordingly abandoned.
(0)
Theory of ignition by human agency.
All godown doors wore found locked, and no bodies were found inside the godown. No pieces of any suspicious mechanism or similar material were found,
There is, accordingly, no evidence to support this theory. (a) Theory of ignition through the agency of Calcium cyanamide.
This theory is only included for the sake of completeness. Stack 41 (on Plan No. 1) consists of calcium cyananide, a synthetic far- tilizer which gives off a small quantity of acetylene gas in contact with damp air,
The theory that such gas might have become ignited outside the godown is most unlikely, as in that case an explosion would have occurred throughout the godown, or at the doors.