( *0 )

in.

The corresponding immersion in the tableis nearly . . . . . l&f

The immersion of the pontoons in an un-loaded bridge being . . . 5-J-

The additional immersion by the weight of*20 men is .... 7-f-

With the small Pontoon .

lbs.

Weight of 20 men .... 3600

Weight of pontoon .... 1729

5329

in.

Immersion corresponding . . nearly 17-’

Ditto, by weight of pontoon alone . 6

The additional immersion by the weight of20 men is . . . . 11-’

The greatest weight of cavalry that can beput in march across the bridge is when movingby double files; and as each horse takes upabout nine feet, (the breadth of a pontoon andits interval) nearly, each pontoon will have tobear one file.