No. 133] 87 



The submarine boat is wholly constucted of boiler iron, con- 

 nected by rivets. In shape it is an elongated ellipse, resembling 

 somewhat the form of an egg; in length it is thirty feet, and ten 

 feet in diameter at its greatest tranyerse section ; it has thirty-six 

 tons of displacement, and weighs 20,000 lbs. At its sides are 

 placed thirty orifices— twenty six of these, which are eight 

 inches in diameter, are filled with bull's-eyes, as is the custom in 

 ships, for the purpose of admitting the solar light into the interior. 

 Of the four remaining orifices, two are used as entrances for men 

 into the vessel ; and the two others at the bottom of the vessel 

 communicate directly with the soil at the bottom of the waves. 

 These last two orifices, which we will call hatchways, are each 

 two feet and a half in length by eighteen or twenty inches in 

 breadth. At the stern of this novel vessel, on its exterior, just 

 above the rudder, is seen a screw propeller, about three feet 

 in diameter, which is sulTicient to propel the vessel without 

 difficulty. Both the propeller and ihe rudder have shafts com- 

 municating with the interior, passing through stuffing boxes. The 

 men in the interior of the vessel can thus guide its motions with 

 facility. 



On the sides, and at the exterior of the boat, are placed, upon 

 hinges, two safety ballast supporters, and suspended by strong 

 chains. 



These safety ballast supporters, which are constructed of wrought 

 iron, resemble in shape a gridiron, and their object is to carry, 

 when desired, a quantity of stone ballast of no value, which 

 loads or lightens the vessels at pleasure in its ascending or de- 

 scending movements. The movemculs of these safety ballast 

 supporters are also governed by ajiparatus in the interior of the 

 vessel. A stout iron bolt, Which passes through a stuffing box, 

 and which may be moved up or down in it, raises or depresses 

 the safety ballast supporters as is desired. 



If we enter the inferior of the submarine boat through the 

 man-hole, we find durselvt'S in an apartment which inextent occu- 

 pies about two- fifths of the vessel; the other three-iifths of its 

 volume being occupied by two laige reservoirs, to which are 

 fitted two pairs of pun)ps, each having two separate functions, 

 either for air or for water. 



