The VOLT, the unit of pressure, is the pressure which, when steadily applied to a conductor whose resistance is one ohm, will produce a current of one ampere.
The WATT, the unit of power, is 1⁄746 of one horse-power, the horse-power being 33,000 lb. raised one foot in one minute. The Board of Trade unit is 1000 Watt-hours.
In carbon lamps of 16-candle power (nominal) about four watts are required per candle power to give good economical results for domestic purposes. One Board of Trade unit will keep a 16-candle carbon lamp alight for about 16 hours; metallic filament lamps require considerably less. {157}
MEASURES FOR SPECIAL PURPOSES
| Stock or kiln bricks | 8 3⁄4 inches × 4 1⁄4 × 2 3⁄4 |
| Welsh fire-bricks | 9 inches × 4 1⁄2 × 2 3⁄4 |
| Paving bricks | 9 inches × 4 1⁄2 × 1 3⁄4 |
| Square tiles | 9 3⁄4 inches × 9 3⁄4 × 1 |
| Square tiles | 6 inches × 6 × 1 |
| Dutch clinker bricks | 9 1⁄4 inches × 3 × 1 1⁄2 |
A Rod of Brickwork 16 1⁄2 feet × 16 1⁄2 feet × 1 1⁄2 brick thick = 306 cubic feet, or 11 1⁄3 cubic yards, and contains about 4500 bricks with about 75 cubic feet of mortar.
Ordinary bricks weigh about 7 lb. each; a load of 500 weighs about 1 ton 11 cwt. 1 qr.
A Piece of Wall Paper is 12 yd. long × 21 in. wide (English), and 9 yd. × 18 in. (French).
Timber and Wood
- 40 cubic feet rough, 50 cubic feet squared = 1 load
- 50 cubic feet of planks = 1 load
- 100 superficial feet = 1 square of flooring
- 120 Deals = 100