W. A., Ellsworth, Maine, asks for information as to the best manner of polishing instruments. We would recommend his getting a piece of buckskin and straining it on a square stick, covering one surface with pulverized rotten-stone, or whiting, perfectly free from “grit.” For the instruments in which ink is used, having unscrewed and opened the hinged joints, clean off the ink first with a wet, then with a dry rag. Next rub the blades on the coated side of the buckskin, and lastly on the plain buckskin, until the appearance is satisfactory. We repeat that the pens should not be put away wet, but be carefully dried and rubbed on the buckskin after use. A drop of watchmakers’ oil on the screws and springs occasionally, will tend to insure the long and good service of instruments. Velvet is the best bed for them in the box; and the mould of their tray would be better cut out of cork than of wood. Any one can fit up his own instrument-case to suit his wants. Our advice is to buy only the instruments you have use for, _and get the best_, keeping them in constant order. L., New York.—We agree with you, the names of streets should be painted on the lamps, and when a light of glass is broken and replaced the name should also be replaced. S. R., Reading, Pa.—The idea is not new. Nay, it is as old as the hills. The ancients used hot air flues under their tiled floors. As long as we use boarded flooring we cannot do likewise, for reasons which any insurance office will freely give you. PUBLICATIONS. We have pleasure in acknowledging the receipt of the first number of THE ENGINEERING AND MINING JOURNAL, a weekly publication which was most desirable to our civil engineers in this country, who have hitherto had to depend for professional information on European sources. The American Journal of Mining was a popular periodical, and this prefixed addition to and modification of its title will go far to increase its well earned fame; for, judging by the specimen number, (and we know that cannot do its future full justice,) this new effort of Messrs. Western & Company is already a success as a most welcome co-laborer in the great constructive art. We tender it our best wishes, and place it on our exchange list.