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Chinese pumps, “ I have introduced the use of them into the United States of America , where they are of great Utility in rivers, in conse-quence of the little labor they require.” (Vol. i, 74.) We are not awarethat they are much used in this country at the present time. The chainpump is employed in the diamond districts of Brazil . M. Mawe, in hisTravels, has figured and described it as used there. Ithas also been re-cently introduced into Egypt , where it is more likely to become domi-ciliated, than the atmospheric and forcing pump, which Belzoni endeavoredin vain to establish; although St. John seems to think even it is rathertoo complex for the present state of the mechanic arts in the land of thePharaohs . “ Windmills for raising water, and chain pumps, have beenintroduced into Egypt ; but as these are machines which require sornere-gard to the principles of good workmanship, they are by no means fittedfor general use.” Egypt and Mohammed Ali, vol. i, 14.
The chain pump, as well as the screw, noria, Chain of pots, &c. hasbeen adopted as a first mover. Placed perpendicularly on the side of aprecipiee, or wherever a small stream of water can be conveyed into itsupper orifice, and can escape from its lower one, the motion of the chainis reversed by the weight of the liquid column acting on the pistons. Awheel similar to the upper one is fixed below, over which the chain alsopasses; and from the axle of either wheel the power may be taken. Apatent for this application of the chain pump was granted in England,in 1784.
There is another device of the Chinese , which is worthy of imitation;and considering the increased security it offers to floating property, andthe additional safety of the lives of navigators, it is surprising that it hasnot been adopted by Americans and Europeans—viz. the division of theholds of ships by water-tight partitions. The Chinese divido the holdsof their sea vessels into about a dozen distinct compartments with strongplank; and the seams are caulked with a cement composed' of lime, oil,and the scrapings of bamboo. This composition renders them imper-vious to water, and is greatly preferable to pitch, tar and tallow, since itissaid to be incombustible. This division of their vessels seems to havebeen well experienced ; for the practice is universal throughout the em-pire. Hence it sometimes happens that one merchant has his goods safelyconveyed in one division, while those of another, suffer considerable da-mage from a leak in the compartment in which they are placed. A shipmay strike against a rock and yet not sink, for the water entering'by thefracture will be confined to the division where the injury occurs. To theadoptioh of a similar plan in European or American merchantmen, besidethe Opposition of populär prejudice and the increased expense, an objec-tion might arise from the reduction it would occasion in the quantity offreight, and the increased difficulty of stowing bulky articles. It remainsto be considered how far these objections ought to prevail against thegreater security of the vessel, crew and cargo. At any rate, such objec-tions do not apply to ships of war, in which to carry very heavy burdens,is not an object of consideration. Staunton’s Embassy, vol. ii, 136.