A Practical Manual On Sea Water Distillation
With A Description Of The Necessary Machinery For The Process

BOARD OF TRADE RULES. 157 30. It is well to keep clean the holes in the feed box, or feed regulator, so that the sea water may pass freely, and without diminution, through them. If gratings are used, as they should be, to strain off impurities, these gratings should also be cleaned. The floats should also be seen to work properly, and not be sticking in the spindles or guides owing to an accumulation of dirt. 31. The evaporator casing is not an evaporating surface, and it is not necessary to clean off the scale too frequently. Scraping it off tends to wear out the casing. . . • Board of Trade Rules. 32. The following is a summary of the rules of the Board of I rade regarding the distilling machinery on board ships :— 33. Where in evaporators, generators, feed make ups, &c., pressure is an essential feature in the process of evaporation, whether such evaporation is produced by heat from coal, gas, steam, or otherwise, the strength, quality of material, and method of construction must be in accordance with the regulations for steam boilers, and they should be examined by the official surveyor on each occasion the vessel is surveyed for passenger certificate, in the same manner as other boilers on board the vessel. All the fittings and mountings of such evaporators should also correspond with the fittings specified for a steam boiler. 34. If the evaporator shell is made of steel plates, all the rules apply just as in the case of the construction of a^steam boiler. It is impossible iiere to deal with all these requirements; reference should be made to a book like Seaton and Rounthwaite s Pocket-book for de-