SUBMARINE BOATS. 



651 



means of 12 oars, which passed through the sides 

 by means of leather stuffing-boxes. The boat, ac- 

 cording to the reports, was completely submerged 

 with its whole crew and the air in the boat was 

 " kept pure by means of liquids," a secret that 

 died with the inventor. An Englishman named 

 Day in 1660 remained under the water in his sub- 

 marine boat at Yarmouth for twelve hours, and 

 came safely to the surface. In his second attempt 

 the boat sank slowly and never was found. The in- 

 ventor as well as the rest of the crew were drowned, 

 and none of the details of the construction of this 

 craft remain; it is only known that it was simi- 

 lar to the Drebbel boat in the fact that it pos- 

 sessed a double bottom which could be filled with 

 water and had to be pumped out to bring the boat 

 to the surface. Papin and Borelli are mentioned 

 as having invented boats in 1672, and Stapleton 

 in 1693, but nothing is known of these attempts. 



At the outbreak of the American War of Inde- 

 pendence, in 1775, David Bushnell, of Saybrook, 

 Conn., built a submarine boat that up to that time 



BUSHNELL'S SUBMARINE BOAT ; 

 VERTICAL LONGITUDINAL SECTION. 



was the most perfect that had been invented. It 

 was of wood, shaped like 2 turtle-shells, back to 

 back, floating in the water tail downward, and was 

 about 7J feet in diameter. It contained air enough 

 to support life for half an hour, and air could be 

 renewed at the end of that time through small 

 ventilators (L and M) by rising to the surface. 

 The operator was seated in the middle, the seat 

 forming a brace between the two sides, and in this 

 position he had his eyes opposite one of the nu- 

 merous glass plates in the cover or top of the boat. 

 In front of him was the handle of a screw (E), by 

 which the boat was propelled; another (F), by 

 which it was raised or lowered; a compass (D), 

 marked with phosphorus; a water-gage (C), to 

 show the depth, marked with oil and phosphorus; 

 and near him the handles or treadles of various 

 small pumps and levers, by which water and foul 

 air were expelled, the rudder moved, ballast let 

 go, etc. The torpedo or submarine magazine 

 (8), as Bushnell called it consisted of a block 

 of oak containing a charge of about 150 pounds 

 of powder. This block was on the upper after 

 part of the boat and connected by means of a rope 

 to a screw (R), the handle of which was directly 

 in front of the operator. The mode of operation 

 was to move slowly along the surface, with the 

 top just awash, till within a short distance of a 

 vessel at anchor, then to sink, and, coming up 

 underneath the bottom, fasten the torpedo by 



means of the screw. The torpedo and screw were 

 then detached from the operator's boat, a clock- 

 work mechanism inside the torpedo being set go- 

 ing at the same time. This clockwork could be 

 set for six, eight, or twelve hours' run, thus allow- 

 ing the operator ample time to make his escape. 

 The boat was fitted with a rudder (G), with 

 water-ballast tank (0) with a valve (N) to ad- 

 mit and a pump (P) to draw out the water and 

 was kept stable by fixed ballast (A) and a re- 

 movable lead weight (B), which when detached 

 by the operator enabled him to come quickly to 

 the surface at any time. In 1776 it is reported 

 that a Continental officer, Sergeant Ezra Lee, at- 

 tempted to attach the torpedo to the British ship 

 Eagle, then blockading New York harbor. But 

 the attaching screw came in contact with some 

 iron part of the ship's body, and in attempting to 

 get another position under the ship he lost his way 

 under the water and had to discontinue his efforts 

 at daybreak. On his return he feared that he 

 had been discovered by the enemy and therefore 

 disconnected the torpedo from the boat in order to 

 lighten her and increase his speed. An hour after 

 his return the mine exploded. The clockwork in 

 the mine was supposed to start at the moment of 

 detaching and had been set for twelve hours. The 

 assertions made by Lee could never be verified, 

 and it is therefore very probable that in the be- 

 ginning he had become frightened and had set 

 the torpedo adrift, and then waited at the surface 

 of the water for daybreak. 



Robert Fulton, the builder of the first steam- 

 boat, began to experiment with submarine navi- 

 gation in 1797, and, after interesting Napoleon 

 Bonaparte, then Consul, in the project, he com- 

 pleted, in 1801, his boat, the Nautilus. This was 

 crudely cigar-shaped, 21 feet 4 inches long, with 

 a mean height of 6 feet, and was built of wood, 

 sheathed with copper and hooped with iron. On 

 the top was a dome with ports for observation. 

 The keel was a heavy bar of metal, which served 

 to keep the boat in equilibrium. When at the 

 surface it was propelled by a sail; when diving 

 the mast was folded downward, and, with the sail, 

 was stowed in a groove in the top of the ship's 

 body. Under water it was propelled by a screw, 

 which the crew turned by means of a crank, with 

 a multiplying motion. The diving and rising to 

 the surface was effected by the filling or pumping 

 out of water in the ballast-tank, which was built 



FULTON'S NAUTILUS. 



in the craft. A rudder was placed at the after and 

 an anchoring device at the forward part of the 

 boat. In June, 1801, the Nautilus received a trial 

 in the Seine, at Paris, and then was taken to 

 Brest, where the inventor, with three men, re- 

 mained an hour under water at a depth of 24 feet. 

 On Aus. 7, 1801, they remained under the water 

 for four hours and twenty minutes by taking a 

 vessel of compressed air with them. He attached 

 a mine to a pontoon and exploded it. Neverthe- 

 less the French Government, as well as the Eng- 

 lish Government, to whom he applied afterward, 

 decided not to follow up his idea. 

 In the twenty years following 1844 Lodner 



