For cutting boiler tubes or pipes, the device being firmly held in place while the work is being done, and the cutters having an automatic and positive feed, the improvement shown in the accompanying illustration has been patented by Patrick H. Benade, of Punxsutawney, Pa, The device comprises two aligned cylinders connected with each other at their ends by rods on which are journaled frames each carrying a cutter wheel. A cone with a longitudinal feather engages a keyway in one of the cylinders, the cone having a threaded shank en-gaged byan internally threaded sleeve which has on its outside a right and a left hand thread, on which screw nuts, levers carried on one of the nuts engaging inclined grooves on the other nut. When the tool is placed in a pipe, and a wrench is applied to the head, causing the cylinders to revolve, the nuts on the sleeve screw toward each other, causing the levers on one of the nuts to travel up the incline of the other nut, as shown at the left in the illustration, the free ends of the levers thus moving into firm contact with the inner surface of the pipe or tube. The continued turning of the cylinders then causes the shank of the cone to screw in the sleeve and feed the cone forward in engagement with the frames carrying the cutting wheels, which are carried around and fed outwardly as the turning continues. The turning of the tool in an opposite direction causes a withdrawal of the cutters and return movement of the cone, with a final release of the clamping levers from the inner surface of the pipe. On the outer cylinder is a gage with gage fingers adapted to set the cutters to the proper point at which the tube or pipe is to be cut off, the fingers resting against the end of the boiler, and being adapted to open and close, that they may be kept as close to the tube as possible loosely, the tool being adapted to cut several sizes. What All Boys Should Know. Don t be satisfied with your boy s education or allow him to handle a Latin or Greek book until you are sure that he can— Write a good legible hand. Spell all the words he knows how to use. Speak and write good English. Write a good social letter. Add a column of figures rapidly. Make out an ordinary account. Deduct 16J per cent from the face of it. Receipt it when paid. Write an ordinary receipt. Write an advertisement.for the local paper. Write an ordinary promissory note. Reckon the interest or discount on it for days, months, or years. Draw an ordinary bank check. Take it to the proper place in a bank to get the cash. Make neat and correct entries in day-book and ledger. Tell the number of yard s of carpet required for your parlor. Measure a pile of lumber in your shed. Tell the number of bushels of wheat in your largest bin, and the value at current rates. Tell something about the great authors and statesmen of the present day. If he can do all this, and more, it is likely he has sufficient education to make his own way in the world. If you have more time and money to spend upon him, all well and good—give bim higher English, give him literature, give him mathematics, give him science, and if he is very anxious about it give him Latin and Greek , or whatever the course he intends pursuing in life demands.—School Supplement. Engineers Licenses. Under a new law. all engineers in charge of power or heating plants in Massachusetts must be licensed, and in order to be licensed, they must pass an examination, arranged by the State authorities. Although enacted last winter, the law only went into operation in August, and the examinations are now open to candidates, who, if the daily papers are to be believed, do not take much satisfaction in them. It will be remembered that the supervising architect of the Treasury Department once wanted some assistants, who, either under the civil service laws or some special provision, were to be selected by competitive examination. The examination was held, but, if we remember rightly, not one of the applicants could pass it, and it was necessary to fill the positions in another way. So with the Massachusetts engineers, as we are told. The examination is a long one, some fifty or sixty questions being proposed, to which written answers must be given ; and it appears that the questions are mainly theoretical, involving principles which can be learned from books, but which working engineers have little occasion or opportunity for studying. The consequence is, as we are told, that the first-class licenses will go to youths fresh from the technical schools, who know all about heat units and calorimeters, but would have considerable difficulty, on starting the engine under their care, in finding the valve for draining the water out of the cylinders, even if the propriety of this operation should occur to them; while the men who have handled engines intelligently and successfully for twenty or thirty years are, as we are informed, in danger of being deprived of their livelihood because they cannot solve a mathematical problem involving the solution of a quadratic equation. How much foundation there may be for these complaints, we cannot say, but it would certainly be a mistake to undervalue experience in such examinations. Of course a man who has greased a locomotive successfully for twenty years might blow up a heating boiler at the first trial ; but on the other hand, algebraic formulas cannot teach the light hand and quick eye of a good mechanic ; so that such examinations should be arranged to test both the theoretical knowledge and the practical intelligence of the candidate, and great skill on the part of the examiner is necessary for this.—Amer. Architect.