EPAULEMENT—EPROUVETTE.

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and be a fair workman in iron, brass, and wood. He should be able to work notonly at the lathe or vice, but also at a smith’s forge. His education should be suchas to make him able to keep accounts, and make notes in his log of all that occurs inthe engine-room. He should have sufficient knowledge of mechanical drawingto enable him, in the event of any important part of the engines being brokenwhen at a distance from any manufactory, to make such a drawing of it as wouldenable a manufacturer to replace it. He should have some knowledge of the firstprinciples of mechanics, a general knowledge of the leading principles of hydrostatics,hydraulics, and pneumatics, without which he cannot fully understand many of theprinciples carried on in the engine, and on which its power depends. Some know-ledge of heat, of the theory of combustion, of ebullition, and of evaporation, may alsobe reckoned as almost indispensable; to which should be added, if possible, anacquaintance with the subject of steam, especially as regards its temperature, pressure,and latent heat.

EPAULEMENT. — It is necessary to notice this word, from the confusionwhich a common misapplication of it is apt to produce. In the true sense of the term,it implies the shoulders or returns made at the flanks of batteries, or at the extremi-ties of parallels; whereas it has been erroneously used to signify the parapet ormerlon of the embrasures, to which these epaulements are appended.

EPROUVETTE.

GENERAL INSTRUCTIONS RELATIVE TO THE PROOF OF GUNPOWDER WITH GUNAND MORTAR EPROUVETTES.

1. Gun Eprouvettes are to be used at all stations for the proof of gunpowder, eitherlarge or fine-grained. The Mortar Eprouvettes are only to be used at Waltham Abbey,Purfleet, Portsmouth, and Devonport.

2. Five rounds of each quantity of powder to be proved is to be the minimum ofrounds for proof in Ireland and at Foreign Stations.

3. At Portsmouth and Devonport, five rounds also to be fired ; but at WahhamAbbey and Purfleet, where proofs are so frequent, (especially in time of war,) andwhere the modes of proof are so well understood, three rounds will be sufficient, ex-cept in such cases as the Officers of the Department see good reason to extend thenumber of rounds.

4. The proof of powder in store to be made annually, at the most favourable seasonof the year. The Reports are to he forwarded to the Director-General of Artillery soas to be received by the end of November each year.

5. As a general principle, the powder in the magazines should be classed in lots of100 barrels, from 10 of which, taken indiscriminately, the samples for proof shouldbe drawn: these samples are to be well mixed, and the proof to be made from themixture. Subsequent proofs for the same lot are to be taken from ten otherbarrels, so that by degrees the whole of the powder in the magazine will be sub-jected to proof; and, as far as can be, none should be issued but such as has beenproved. It is always to be understood that such barrels are to be preferred forproof as, from local circumstances, may be presumed to be in the least good con-dition.

6. In the event of the samples of the first ten barrels not coming up to the stand-ard, it is clearly to be understood that the remaining 90 barrels are not to be con-sidered equally deficient in strength without further trial.