A subscriber in North Carolina wishes to know where he can get the best machinery for making linseed oil, as he is about to commence its manufacture. We cannot give him the exact information which he wants. It would be well for manufacturers of machinery mdash;all kindsmdash;mills, c, to advertise in our columns, once at least, in every volume. We are positive that it would put far more than the price of advertising into their pockets, it would save us much trouble, and be of great benefit to many of our readers. Manufacturers and others who use and wish to purchase machinery look to our columns for information. We have no occasion to make these remarks for the purpose of obtaining advertisements. We do not speak from pecuniary motives, although we admit that advertisements of machines are advantageous to us for the reasons given before, that those who use machinery look to the Scientific American as the source of obtaiaing information about the same. In this respect we derive a benefit, but much more the ma- nufacturing advertiser, and those who require such information. J|We are constantly receiving enquiries from every part of the country concerning the price of various machines and tools, and the address of the manufacturers. Those manufacturers who make machines for turning, mortising, sawing, tenoning, planing, tongueing, and grooving, etc., etc., who will send us circulars, stating capacity and price of each size will find it for their interest to do so, besides it will render us better able to give our patrons reliable information. Not a day passes but we have enquiries (besides receiving a number of letters), made at the office, for the address of some manufacturer, or to know which machine in some particular branch of business is the best. To answer these incessant enquiries it takes much time, and cannot always be done satisfactorily, whereas, if our manufacturers will send us lists of what they manufacture, we will paste their circulars in a portfolio, and keep them in a conspicuous place for the benefit of such as may be in pursuit of machinery or tools, and no doubt both sellers and purchasers will be benefitted thereby.