W. M. R.—Boys ranging in age from fifteen to eighteen years, from any part of the country, may enlist as naval apprentices on the U. S. training-ships, but not on the school-ships Saratoga or St. Mary's, which are, in reality, local institutions, supported by New York city and Pennsylvania. An excellent idea of the requirements in either case may be gained by reading the articles headed "The Nautical School of New York City," in No. 35, Vol. 8, and "Uncle Sam's Ships," in No. 18, Vol. 10. The school-ship boys serve but two years, while the naval apprentices remain until they reach the age of twenty-one, unless sooner discharged for misbehavior or disability.

134.—1. In military or naval parlance, a ration is a portion or fixed allowance of provisions, drink and forage, assigned to a soldier in the army or a sailor in the navy, for his daily subsistence. Its component parts are established by law, but may be varied by the Secretary of War or of the Navy; or, when necessary, by the senior officer present in command. The latter may also diminish the allowance, in case of necessity, but of course the persons whose allowance is thus lessened are reimbursed according to the scale of prices established at the time of such diminution. 2. The regulation chest measurement required of a seventeen-year-old applicant for admission on a training-ship is 29 inches.

F. B. H., Midshipman and W. H. E.—1. As there are but two schoolships in the United States, and none but New York and Pennsylvania boys are admitted on them, non-residents' applications for enlistment would not be considered under any circumstances. Boys desiring to enter the U. S. navy can do so by enlisting on a training ship, which is a government institution, and intended as a means of fitting our youth to perform the duties of sailors and petty officers in the regular navy. The schoolship boys, on the other hand, are trained for the merchant service. The Chief of the Bureau of Equipment and recruiting, Navy Department, Washington, D. C., is the one to whom all applications for enlistment on the training ships should be made. 2. No premium is offered for U. S. pennies coined in 1858.

General Napoleon.—1. A graduate of the schoolship Saratoga might be able to obtain an appointment as quartermaster on an ocean steamship at a salary of about $30 per month. The other officers on these vessels are shipped on the other side of the Atlantic, and have to show a certificate of service before being appointed as mates or to any other official position. The schoolship boys should experience but little trouble in getting some minor berths on coastwise vessels or other crafts sailing under American colors. The chief idea in establishing the two schoolships, St. Mary's and Saratoga, was to fit boys for the mercantile marine, and probably, if ever the trans-Atlantic liners sail under our flag, they will be given appointments on them. 2. The pay of the officers on steamship lines varies so greatly that no general average can be given.

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.

M. S. S.—1. The sun's average distance from the earth is about 93,000,000 miles. Since the orbit of the earth is elliptical, and the sun is situated at one of its foci, the earth is nearly 3,000,000 miles further from the sun in midsummer than it is in midwinter in the northern hemisphere. In the southern hemisphere, these conditions are exactly reversed. 2. U. S. Senators are elected by the legislatures of the States they represent, while members of the National House or Representatives are elected by the people. 3. It is not considered improper to write a short message or letter on a half-sheet of paper; in fact, some styles of writing paper consist of but a single sheet. 4. The use of a moderately stiff tooth-brush, clean water and castile soap will keep the teeth white and in good condition. Tooth-powders are injurious. 5. Nickel-plating should not be exposed to dampness, and must be kept bright by wiping with a soft rag.

Captain Chap.—The total population of the earth is estimated at 1,480,000,000—of which Europe has 357,000,000; Asia, 826,000,000; Africa, 164,000,000; America, 122,000,000; Australia, 3,500,000; the Oceanic Islands, 7,500,000. The density of population is greatest in Europe—Belgium standing at the head, followed by the Netherlands, Great Britain and Ireland, Italy, Japan, the German Empire, China, British India, Switzerland, France, Austria, Denmark, Portugal, Spain, West Indies and the United States. More than one-fourth of the human race is found in China and Japan, the former counting 350,000,000 and the latter 40,000,000; more than one-fifth is in India, 324,000,000, of which 286,000,000 belong to British India. The only one of the chief European States that exceeds this country in population is Russia, with 93,000,000. The others range thus: German Empire, 49,000,000: Austria-Hungary, 41,000,000; France, 38,000,000; Great Britain and Ireland, 38,000,000; Italy, 30,000,000; and Spain, 17,000,000.

Lelia and Philip.—1. A high-class eight-wheel passenger locomotive engine costs about $8500. 2. The strength of a steam engine is commonly marked by its horse-power. By one horse-power is meant a force strong enough to raise up 33,000 pounds one foot high in a minute. James Watt, the noted mechanician, engineer and scientist, famous as the improver, and almost the inventor of the steam engine, established the horse-power unit, and the figures were fixed in the following curious manner: He found that the average horse of his district could raise 22,000 pounds one foot a minute, and that this was the actual horse-power. At that time, however, Watt was employed in the manufacture of engines, and customers were so hard to find that it was necessary to offer extra inducements. So, as a method of encouraging them, he offered to sell engines reckoning 33,000 foot-pounds to a horse-power. Thus he was the means of giving a false unit to one of the most important measurements in the world, as, in reality, there are no horses to be found that can keep at work raising 33,000 pounds one foot a minute.