The invention here illustrated belongs to that large class of inventions now being patented, which relate to improvements in the detail s of operating mach i n e ry. W h en i m p r ove m e n t s are applied, as in t h is case, to mac h i n e ry i n ge ne ral, the p at e nts are more likely to be pro fitabl e to the owners than, pe rh aps, any other class of patents whatever. This is an i m prove d bel t s h i fte r, and, in som e respects and in many si t u a t ion s, seems to possess a d v ant ages over any other that we h av e s een. The cut rep res e nts a ver t ical section of the apparatus, with two pulleys, A and B, upon the same shaft, the pulley, A, t u r ning loos el y upon the shaft, and B bei ng keyed firmly to the shaft, so as to carry the shaft with it i n its rotations. The shifter is re p re sen ted in the cut in position to hold the belt upon the tight pulley, B. The slide, C, with its two jaws, e and [, embracing the belt, is fitted to sl ip back and fo r th on the bar, D, carry i ng the belt alon g i n its m ove m en ts, an d thu s sh i ft i n g it from o n e pull ey to the other. W hen in the pos i tion shown in the cut, the end of the el bow-sh ape d lever, g, enters the notch in the bar, D, and thus holds the slide, C, securely in pl ace. Now, if' it is desi re d to s t op the machine by shifting the belt to the loose pulley, A, the operator draws the cord, 7, which first lifts the end of t he lev er, g, out of the notch, when a continued p ul l upon the cord draws the slide, C, al on g till the ? end of the lever, h, falls into the notch, where it is firmly held by the s pri n g, i. By drawing the co rd, k, the belt is shifted back upon the tight pulley, B. Behind the levers, !I a n d h, pins are pl ace d to stop the levers from being drawn too far over. The cords, j and k, may be led in any direction, or th ey may both be attached to a 1 ever SQ a s to be operated by mov ing t he end of the le v e r back and fo rth. Patents for this val u abl e invention have been secured, th rough the Scientific American Patent Agency, in France, Great Britain and the United States, the American p a te nt h eari ng date Aug. 14, 1860. F u r th e r information in relation to i t may be obtained by addressing the inventor, John C. Goar, at Binghampton, N. Y., or F. Z. Seymour, No. 27 State-street, Boston, Mass THE WATER GAS EXTINGUISHED.We see by the Philadelphia papers that the lighting of the Girard House by the water gas has been suspended for "re-pairs," and a legal de m a n d has been made on t he gas trustees to have the house supplied with the coal gas from the city w ork s. Some of the pi pe s were found to be so filled with tar that it was found necessary to clean them out before the city gas could be'lntroduced. The reconciliation of this foct with the s ta teme n t that th e water gas contain e d n o con d ens abl e prod u cts, would afford a fine field for the ingenuity of Philadelphia lawyers. ARTIFICIAL FISH BREEDING.This is becoming quite a business in some portions of our country, and we do not see why it should not prove successful. A Mr. Kellogg, of Hartford, Conn., has already in the comse of his e x peri m ents, succeeded in producing by art i fi cial means, over 1,000 tront,'which are now d oi n g well. He has lat ely sailed for France to procure further in form a ti on from the great fish b re ede rs of that e ou ntry. On his return, it is said, he will be j o i ne d in the business by Cot Colt, of pistol ntrietiy.