at every division, so as to admit a locking piece D, the rotator having revolved for a little time, lets go the locking piece, which falls into some one of the spaces on the divided plate C C, whichever way the current may have carried the register. The mariner letting the machine remain in the water a limited time, on drawing it up he must examine the register, and compare it with the time it has been in the water; by which means he is able to determine the rate of the current, and, by examining the points on which the register is locked, he is likewise enabled to judge of the course the under current is setting to, although the upper current may be running a dif ferent way. F, is an axis, which the regulator turns on. G, the friction roller. HI, a balance for the register. L, an endless screw, which acts in a wheel of twenty teeth; the axis of which has a pinion of six, and acts in a wheel of forty-two teeth. On the axis of this wheel is fixed a hoop, which is moved or set by an index or circle S. When this index is set to S, lift out the locking piece at D, and the upper end of it will pass an opening in the hoop, at which time turn the index from S half a circle either way, which will prevent the locking piece from falling until such time as the wheels move the index back to S. The last-mentioned axis has a pinion of seven, and acts in a wheel of forty-four teeth, the axis of which has a pinion of six, and carries the indes round a circle, which is graduated into twelve parts, each answering to the twelfth of a mile. The last mentioned pinion has a wheel of sixty teeth, and carries an index the reverse way round a circle every ten miles, and is marked from one to ten. Care should be taken in fixing the vanes on the tubes, so that when the rotator is immersed in the water it may lie in a horizontal position. The vanes, as fixed on the abovementioned mentioned tube, leave the but-end of it clear four inches and three quarters. The rotator being put together, should be fixed on its centres, so that it may move freely, and if the vanes should not prove of equal weight, the heaviest must be reduced till the rotator become poised; this will be an advantage to the rotator in very slow sailing. The most essential parts of my improvements are as follows: first, in respect to the sounding machine, the chief object of which is to do away or lessen the errors arising from the old method of taking soundings, as the chief guide for the mariner by that method is to judge of the perpendicular depth by length of line out, which is very apt to deceive him a great deal, whereas, on the above principle, he is governed by the descent of the sounding weight only, without paying any respect whatever to the length of line except in case of using the reel. My improvements in the rotators are the invention of the air tube and the method of adjusting or regulating it. A rotator on the above-mentioned principle will answer both for quick and slow sailing, and give the true distance, in both cases, without any danger of its breaking the register in quick sailing by holding too much water. These are advantages which no former rotator ever possessed, and that the mariners may be able to determine whether the rotator has met with any accident, f make a steel gauge, one end of which I fix in a dot nearly at the extremity of the vane, the other end reaches to the next vane. I make a mark on it, and so contrive the process until all the vanes are marked; and as they are fixtures, their marks always remain at the same distance from each other. If the rotator has not received any any injury, notwithstanding the rotary motion may be altered by the regulator as before described, the vanes still remaining stationary, so that the mariner may be assured whether the rotator has received any injury by applying the gauge as above stated. The registers may be made of brass, or any other fit materials. In witness whereof, &c. Specification of the Patent granted to JOSEPH SMITH, of Red Lion-street, Holborn, in the County of Middlesex, Smith; for a Mode of fixing and setting an Alarum, or Alarm Bell, so contrived as to alarm and awaken Families in case of Fire breaking out, or Thieves entering the House, by Night or Day. Dated August 19, 1802. With a Plate. To all to whom these presents shall come, &c. Now KNOW YE, that in compliance with the said proviso, I the said Joseph Smith do hereby describe and ascertain the nature of my said invention, and in what manner the same is to be performed; that is to say: The plan of the said alarum, or alarm bell, and the mode of its being fixed and set, is described and ascertained in and by a drawing at the top of these presents, intended to be enrolled herewith (see Plate IX). And the said alarum, or alarm bell being fixed at the upper or most distant part of a house, will be set going by any of the lines represented by letters V, V, (which are conducted to any part of the house,) either taking fire or being cut by the opening of the door, as at letter W or letter S, or the pin being removed to which it is affixed in the window or window |