G The pipe to discharge the Mephitic air,
H.H Two air pipes to let the air out of the water chambers; they mount to the highest part of the Vessel to let the air in when the water is discharging; there should be at least four of these pipes; two in the bow and two in the stern; they may be lead from the stem along side and unite at I.I there the two mounting pipes H.H will be suffecient, care must be taken that the air can pass off with ease from all parts of the water chambers, or they cannot fill, nor can the vessel be got under water,
C The balancing chamber.
D The safety pump
E The discharging pipe
J Is a valve to let the water go from the centre chamber to the two ends, but not return, by this means water may be drawn from either end to balance the Vessel horizontal there are four such Valves,
All the communications with the exterior have cocks as will be seen in plate the third,
Plate the Third one inch to a foot,
Figure the first shews a section of the double forcing pumps A and B too cocks to draw the water from the right and left water chambers.
Figure the second a side View of the pumps A the pump B the valve which lets the water pass into the body of the pump C the valve which discharges the water by the cock and pipe D by shutting all the cocks and screwing off the top plates which cover the Valves they may be cleaned and put in order though the vessel were under water, Near the pump the plunging anchor F has a cock to stop the water in case the cable should break. E is a screw on which the anchor cap rests while the anchor is up and thus its weight is taken off the cable,