Our engraving illustrates a convenient little implement for sharpening knives. The top and bottom pieces are of porcelain, the bottom of the top piece and the top of the bottom piece being recessed to admit the convex emery disks, A. PHOTOGRAPHIC PRINTING APPARATUS. apparatus been on the Milwaukee and Lac La BeSg, when they met on the St. Clafl' flatS; 'even at the late moment when the dire warning note was sounded, collision could have been easily avoided. The whole steam power of the vessels thrown instantaneously (as is possible) upon the taut wire rope rudder lines, it would have swung them so as to merely rub sides, if they touched at all. I have watched with admiration, on the rapids of the St. Lawrence, the old Indian pilot with his half dozen brawny assistants, grouped around the mammoth wheel, as with lightning speed he shot the long sault or plunged the cascades. I have watched his quick, nervous action and word of command so quickly sounded by his assistants, and wondered what our fate wouldbe should these men mistake, even for an instant, larboard for starboard. But with a machine like this the doughty old red-skincould stand in all his native dignity alone, and with one hand, unaided, as lightly as a feather, make the steam power, as prompt as, telegraph, work his wayward and oft-changing will, and swing his steamer as quick as changing a top. Another beautiful contrivance connected with this, and one as much to be appreciated by the traveling public as the steam rudder by the regular marine, is what the patentees. technically term the “life lines.” If you will call back to memory almost any marine disaster from burning, either at sea or on our inland waters, you will readily recollect that generally the most painful and terrible portion of the calamity began when the ship lost steerage way and was going adrift— going any and every way before the wind. From the Henry Olay on the Hudson, to the Sea Bird on Lake Michigan, it has almost ever been the same story ; a pilot-house deserted; a vessel unmanageable; refuge within almost easy reach, impossible of attainment by lack of steering power. This apparatus provides continuous communication from stem to stern, by which the vessel can be managed from any part of the deck. When the pilot-house gets “ too hot to hold him,” the wheelsman can take hold at the next cool spot. If the stern is in flames he can steer from the bow, and vice versa. as long as there is a bit of deck left the iron life-line is there, and until it melts the communication is as complete. The two parts are held together by a vertical screw, B. In use the left hand grasps the top, and the bottom is pressed down upon a table. The edge of the knife to be sharpened is then drawn by the right hand through between the emery disks, the convexity of these disks, enabling a strong pressure to be brought to bear upon it, and, as a consequence, a rapid action upon the blade is secured. Its appearance is tasteful, and it will be found a desirable Inventors who contemplate taking out Letters Patent should read the instructions given in another column, which fully explain the systern.upon which the proprietors of this journal manage their extensive Soliciting Agency. We are always happy to advise with inventors, and wilf furnish them all .the necessary instructions how to procwd upon application to us, either in person or by letter. Ifiventors and patentees will find at our office the Official Patent Reports, Decisions, and Claims, which they are at liberty to examine. We shall be glad to afford them every possible facility.