CURIOUS READER.--1. There are several colleges in this country in which poor boys are afforded an opportunity of putting into practice legitimate plans for raising sufficient money to pay for tuition and other expenses. This subject was treated of in a very interesting and instructive article entitled "Working One's Way Through College," in No. 15 of the volume just ended. In it will be found many such plans, which will prove of great benefit to those intending to thus gain a collegiate training. 2. The Constitution does not require candidates for government positions to possess a college education--in fact, comparatively few heads of departments, commissioners, etc., are thus equipped. 3. There are no "free trade" colleges in the United States. We do not know of the existence of such institutions in any part of the world. L.G.C.H.--1. In soldering, the edges of the metals to be put together must be perfectly clean, to insure which, as well as to counteract the oxidization which most metals undergo when heated, a flux is used which neutralizes these otherwise serious impediments, securing a firm joint. Borax, rosin, sal-ammoniac, common salt, limestone, glass and several other substances are used for this purpose, according to the nature of the metal used. Rosin or oil is usually employed in soldering tin and lead, while a mixture of muriate of zinc and sal-ammoniac is used with steel. 2. A complete outfit for printing an amateur paper such as that you describe will cost at least $200, and can be purchased from any dealer in printing materials. 3. Construct the camera according to the plans laid down in Vol. 9, No. 34. The cost of that issue will be 6 cents, postage free. J.H.R.--Numerous articles on how to construct cabinets, bookcases, etc., have been published in previous volumes of this paper. Among these are the following: "How to Make a Refrigerator," "Cabinet-Making for Beginners" and "Screens and How to Make Them." Nos. 35, 47 and 48, Vol. 5; "How to Make a Desk," "Hanging Bookshelves" and "Corner Cabinet," Nos. 7, 15 and 22, Vol. 6; "Hanging Cabinet," No. 16, Vol. 7; "How to Make an Amateur Carpenter's Bench," No. 36, Vol. 8; "How to Make a Portable Bookcase," No. 2, Vol. 10, and "How to Make a Bookcase and Cabinet," No. 8, Vol. 12. These numbers will cost six cents each, no charge being made for postage. It is our intention to publish such articles in this and succeeding volumes, whenever the opportunity is presented of giving the boys novel and useful ideas in the "how to make" line.