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be pretty well filled with the gas.

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Ten rats and thousands of dead cockroaches were lying about the floors, &c., after the operation.

next treated one by one, The several compartments of the vessel were commencing forwards. The capacities in cubic feet of these compartments, each of which consisted of a hold and 'tween decks, were as follows :-

No.

Hold.

'tween Decks,

Total

Tous.

Tons.

Cubic feet.

1,369

524

79,720

2

1,779

699

99,120

3

817

335

46,080

1

1,393

637

81,200

941

557

58,240

364,360

Total

Each

Each compartment had four ventilators, about 11⁄2 feet in diameter. ventilator opened into the 'tween decks, an inner tube, about 14 inches in diameter, being, however, continued down through the main-deck into the hold As some space was left below, and ending at the lower side of the main-deck. between the top of the cargo and the main-deck, and there was also a free space between the cargo battens and the plates forming the sides of the hold, the gas could pass freely to the bottom of the hold on each side. The cargo itself was very closely packed.

The gas was introduced by putting the hose down a ventilator, the return pipe being usually put through a partly-opened hatch, and the other ventilators closed with canvas. The process was continued until the gas began to issue in a concentrated state from the hatch, an hour or more being usually devoted to each compartment; No. 4 compartment, which was empty, received less of the gas. The saloon, with the cabins opening out of it, the galley, and the space under the poop-deck were similarly treated. The engine-room, stokeholds, and coal bunkers were not treated. The gas was introduced into the saloon through a ventilator in the entrance passage. It was dark at the time, and the electric lamps were left lit, so that I could observe through the windows the behaviour of the gas in the saloon. It gradually filled the room from below upwards, the Above this layer upper surface of gas having a fairly well defined surface. flies still alive could be observed until the upper level of the gas reached them, when they were killed.

In the holds which were full the gas would doubtless tend to pass down the free space at the sides of the hold between the cargo-battens and side plates, and thence inwards through the cargo. As the cargo was warin (the bags of seed had a temperature of about 100° F.), the air would naturally circulate down the sides and upwards through the cargo; and the introduction of a heavy gas, such as sulphurous acid, would increase this circulation. The cargo was, however, very densely packed, and it would probably take a long time for the gas to thoroughly penetrate. Unfortunately for the observations there were very few rats on the ship.

Before leaving Dunkirk I was able to examine Nos. 4 and 5 holds pretty thoroughly. No. 4 was practically empty when treated and was left with the ventilators and hatches closed for about 12 hours after the operation. After the ventilators had been open for several hours I descended to the bottom. One dead mouse and several dead crickets were seen lying on the limber boards at the bottom; living crickets were, however, heard chirping in both the 'tween decks and holds. The gas bad thus not been sufficient to kill all the crickets-doubt- In No. 5 hold, which had -less because the treatment had been too hurried.

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been full of jute and bags of seed, I also heard crickets chirping, but could not find either dead or living rats or mice. As to No. 1 hold, Captain Lind- quister reported to me that two live rats and five mice were found and killed after cargo was discharged, and that several others were seen running about. In No. 2 hold three live mice were found and killed, and more were seen running As the holds were kept closed, except about, besides a number of live crickets. when the work of discharge was actually going on, it seems hardly possible that these animals could have got in after the operation of disinfection had been completed; and evidently the penetration of the cargo by the gas had been very imperfect.

With regard to the question of damage, the cargo, so far as I was able to judge from superficial examination, appeared to be quite uninjured. Much evidence as to absence of damage in certain common articles of cargo has been presented in a paper by Dr. Duriau, Officier de Santé at Dunkirk, and These gentlemen M. David, Chemist to the Chamber of Commerce, Dunkirk. kindly shewed me a number of samples of coloured fabrics and various other articles which had been thoroughly exposed to the action of gas from the Clayton apparatus, together with the corresponding control samples; and the appearance of the samples entirely lore out their published statements.

The

In the saloon and staterooms I could observe no evidence of appreciable damage, although everything, including articles of clothing, had been left exposed to the gas. The tarnishing of brass fittings was quite superficial and easily removed. On the other hand, the sinell left behind in the bedding and various woollen materials, such as cloth, &c., was extremely unpleasant. bedding and clothes continued to give off an unpleasant sinell for some days at least, although they were taken out and thoroughly aired. I slept in one of the staterooms after the disinfection, and although the bedding had been aired on deck, and all windows and doors left open for several hours, the atmosphere was most unpleasant. Two ladies who slept on board suffered For at least a week afterwards considerably from catarrh of their air passages.

the bedding and clothes had a most unpleasant smell in spite of constant airing. The smell was due to some other compound than sulphurous or sulphuric acid, as it was distinctly suggestive of putrefaction. Captain Lindquister reported to me from Cardiff, ten days after the disinfection, that "the smell is still with us," and my own clothes, which had been left in one of the staterooms, still smelt very distinctly sixteen days after disinfection, and in spite of all efforts to get rid of the smell by airing. The smell left by the Clayton process would evidently be a somewhat serious inconvenience in the case of passenger vessels.

"

As regards the failure of the gas to thoroughly penetrate the holds of the Bavaria," I believe that this was due to insufficient time being given to the operation. There is no doubt that if the gas were given sufficient time it It seemed to me that what was needed would destroy every living animal.

was that the process should be so carried out that gas should be passed in slowly for several hours into each hold. If the gas is passed in too quickly it simply flows over the surface of the cargo and comes out by the nearest ventilator. It would be best to treat all the holds simultaneously and utilize the time so gained by devoting a sufficient number of hours to each hold. The gas would thus have time to penetrate sufficiently to kill all rats, mice, and insects with certainty. It must be remembered that sulphurous acid does not diffuse readily, and that it is probably liable to be absorbed to a considerable extent by articles of cargo.

For the treatment of a hold full of cargo the Clayton process possesses certain very distinct advantages which it may be well to mention in connection with my previous reports. In the first place the process of filling the hold can be carried out simply by gravitation. The gas must in time find its way to the bottom because it is heavier than air. Any hold can thus be treated, whatever the construction or system of ventilation may be. In the second place the process is perfectly safe. There is not the slightest risk of fire or explosion,

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PUBLIC RECORD OFFICE

Reference :-

C.O. 885

8

PUBLIC RECORD OFFICE, LONDON

ALLY WITHOUT PERMISSION OF THE BE REPRODUCED PHOTOGRAPHIC- COPYRIGHT PHOTOGRAPH-NOT TO

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