as found to be such an excellent vessel that her
dimensions were adopted for the _Thunderer_, laid down about 1758. One
of the most interesting models in the Museum is of the _Triumph_ (74),
also built on the lines of the _Invincible_ in 1764. Her length of
gun-decks was 171 ft. 3 in.; breadth, 49 ft. 9 in.; depth of hold, 21
ft. 3 in.

In the following year was built the _Victory_, 100 guns, famous as
Nelson's flagship at Trafalgar, and still afloat in Portsmouth Harbour.
Her dimensions are: length of gun-deck, 186 ft.; breadth, 52 ft.; depth
of hold, 21 ft. 6 in.; tonnage, 2,162.

[Illustration: FIG. 55.--The _Royal George_. 1746.]

The following table gives the dimensions of typical ships of war
constructed about the middle of the eighteenth century:--

---------------+---------+---------+---------+---------+---------+--------
Number of | 100 | 90 | 80 | 74 | 64 | 50
guns. | | | | | |
---------------+---------+---------+---------+---------+---------+--------
Length of | 178 ft. | 176 ft. | 165 ft. | 171 ft. | 159 ft. | 146 ft.
gun-deck | | 1 in. | | 3 in. | 4 in. |
| | | | | |
Length of keel | 143 ft. | 142 ft. | 133 ft. | 138 ft. | 130 ft. | 120 ft.
for tonnage | 6 in. | 7 in. | | 8 in. | 9-1/2 in.| 8-1/2 in.
| | | | | |
Extreme | 51 ft. | 49 ft. | 47 ft. | 49 ft. | 44 ft. | 40 ft.
breadth |9-1/2 in.| 1 in. | 3 in. | 9 in. | 6-1/2 in.| 4-1/2 in.
| | | | | |
Depth of hold | 21 ft. | 21 ft. | 20 ft. | 21 ft. | 18 ft. | 17 ft.
| 6 in. | | | 3 in. | 9-3/4 in.| 2 in.
| | | | | |
Tonnage | 2,047 | 1,827 | 1,580 | 1,825 | 1,380 | 1,046
| | | | | |
---------------+---------+---------+---------+---------+---------+--------

The genuine frigate--that is to say, a large cruiser, of relatively high
speed, carrying its main armament on one deck--was introduced into the
Royal Navy in 1741, when the _Adventure_ was built. She carried
thirty-two guns, of which twenty-two were 12-pounders. The firs