In answer to the inquiry put by " B. G.," who is desirous of learning the most effectual mode to prevent his 5-8ths rod-iron fence from being entirely destroyed by rust, I beg to inform him, the cure for iron sickness is to have it galvanized (which means coating it with zinc). The, metallic contact between the zinc and iron immediately suspends the destruction going on with the latter, because the zinc is lowest in the scale, and is the more easily oxydized of the two. This plan was well known to Sir Humphrey Davy, and has been lectured on by Prof. Brande, of the Royal Mint. I write from my own experience, having had some rustyjgarden tools galvanized, thatjhave since been four years in use, and are quite perfect.—(The Builder.- [It will be no easy matter to galvanize a rusty wire fence ; but it certainly would be a good plan to prepare wire for fences by galvanizing it before it is offered for sale. If vrusty wire is rubbed with: boiled oil, in which some red lead has been mixed, on a warm day, the rusting process will be arrested. The tartrate ot soda, is a good and agreeable substitute for common sulphate of magnesia, as a purgative. Ten drachms is a medium dose. The Crystal Palace is going to be surrounded with groggeriea, unless the Common Coun-eil shuts them out.