( 107 )

jl. in.

C D, the breadth above, is . 4 7{-

E F, the breadth below, is . 4 3^

C E, I) F, the depth, is , 2 lj

The fore and after peaks are each 2 ft. 4 in.long, and are 2 ft. 9 in. wide at the ends. Thepeaks rise 8 inches above the central part.

These pontoons are very little used, and in-deed could not be of much use.

Fig. 15 and 16 represent the Prussian tinpontoon.

ft. in.

The length above is .19 3f

The length at bottom is . 16 2-g-

The breadth, C D, fig. 16, is . 4 0|

The depth, CE, DF, is about 1 10£

The defects of our tin pontoons have alreadybeen pointed out, pages 58, 71, fig. 15, plate 2;and frequently experienced, pages 62 and 70;and although, by decking or covering them insome way or other, some of the disadvantages,and accidents, to which they are subject, maybe obviated, yet nothing can render them fit tobe applied, with safety, in the passage of great,turbulent, or rapid rivers. For such services,boats of boat-like shape should be provided; and,whether in selecting, altering, or constructingvessels for such operations, there can be nodoubt, that, under whatever modifications it may