52 ANNUAL OP SCIENTIFIC DISCOVERY. 



IMPROVEMENT IN COMMUNICATING ROTARY MOTION. 



At a recent meeting of the Franklin Institute, Mr. Jones called the 

 attention of the members to a simple contrivance for communicating rotary 

 motion, without the aid of toothed wheels, or belts, invented by Mr. Joseph 

 Thatcher, of Philadelphia. It is believed to be new, and consists of a rigid 

 bar whose ends are fitted to the pins of cranks secured on the shafts that 

 are intended to transmit and receive the motion. In the middle of the bar 

 is a slotted hole, of a length rather more than the throw of the cranks. A 

 stationary pin is secured in line with the centres of the two shafts, and (in 

 the present instance) equi- distant from them. Upon this pin the slotted 

 lever is free to slide, in the direction of its length. When one shaft is 

 turned from right to left, the crank pin carries the attached end of the bar 

 with it ; the fixed pin in the slotted hole, preventing any motion sideways, 

 the other end of the bar is obliged to move in an opposite direction, or 

 from left to right ; the motion of the bar gradually changes from a vibra- 

 tory, to one in the direction of its lengths, and vice versa. The model 

 shown worked freely, no undue friction being apparent. Jour. Frank. 

 Institute, August, 1854. 



REMOVAL OF THE WRECK OF THE UNITED STATES FRIGATE 



MISSOURI, AT GIBRALTAR. 



One of the most difficult, and at the same time successful, sub-marine 

 operations ever undei taken, was the removal of the wreck of the U. S. 

 Steam Frigate Missouri, which was burned and sunk some years since, in 

 the harbor of Gibraltar. She careened as she went down, and laying 

 upon her beam ends, presented one of her shafts upwards, very near the 

 surface of the water. This mass of iron was 19 inches in diameter, and 

 of course, offered a dangerous obstruction to the bay. The existence, 

 moreover, of so vast a body as the sunken frigate, at the bottom of a har- 

 bor in which the tides ebbed and flowed, and strong currents continually 

 shifted the sand, was not to be tolerated in a port, so important to the 

 commercial and war marine of Britain, as was Gibraltar. The British 

 government accordingly presented the case to the cabinet at Washington, 

 and requested the removal of the obstruction. This was at once agreed to 

 by the authorities at Washington. The British Secretary, conceiving the 

 job to be a very bad one, kindly recommended to our government, as very 

 suitable engineers of the work, Messrs. Lovi and Marshall. These gentle- 

 men had acquired a great reputation in England, by raising the line-of- 

 battle-ship, the Hoyal George, which sank so suddenly, at Spithead, and 

 carried down with her hundreds of men and women. Our Navy De- 

 partment employed these engineers to raise the Missouri. They went to 

 Gibraltar, and worked faithfully for three long years, at the noble hulk 

 under water and then reported to the Department at Washington, that 



