having an interest in the present state of feeling with regard to the trustworthiness of steamships built in the most modern style, we publish an article from Engineering, on the brenking of the steamers Chusan and Mary. Al the same time, we must feel some surprise that a puper generally so well informed as Engineering, should not have made itself acquainted with the peculiar circumstances which the steamer Chusan was intended to suit. It may, as it suggests, require little ability, when called on to reduce the price of a ship, simply to lessen the scantlings of the several parts, but this was not the sole principle involved in the case of the Chusan. That steamer was built to suit certain circumstances, which were very different from those for which steamers in England are generally adapted. In other words, she was essentially a river steamer, and intended to navigate a stream where, although in summer there is sufficient depth of water for large sea-going ships, the winter level falls so low that a few inches may muke the difference between the poslity of getting over the bars which interfere with che channels, or having to discharge her cargo into lighter draught vessels, The strains in perfectly smooth water like the Yangtsze, are totally different from those to which an ordinary sea-going steamer is posed. There are few conceivable circumstances under which a vessel engaged in such navigation could be exposed toa strain linble to test ber longitudinal strength. She has no waves to surmount, reversing at each moment the conditions of the load to be carried, and practically has to be little stronger than would be a box to hold her ordinary cargo when placed on a fiat floor, While longitudinal strength, as a girder, which is an essential requisite in ocean-going steamers, can thus be reduced to a very great extent in those intended for river traffic, it is in the last degree essential that the weight of the Jatter should be reduced to the lowest limits, in order to enable them to travel at all when the water is low. The high sides of the sea-going steamer must thus be dispensed with, and without high sides and deep holds the requisite conditions of strength as a girder become greatly diminished. With regard to thicknessof plates the conditions are very similar. If they are sufficient to prevent bulging when loaded, they will answer all the purposes intended. OF course, beyond this, a considerable limit has to be allowed for rust and wear and tear, but as none of
Text read from the printed page and cleaned; old type leaves the occasional error.