Transmitted in all directions. Effect of boring hole in side of vessel containing a liquid.
Pressure increases with depth.—Experiment. Lower into jar of water cylinder closed at bottom by glass disc, the pressure of the water supports the disc. Pour water into cylinder till bottom falls, the lower the cylinder is sunk, the more water is required for this.
Liquids find their level.—Experiment with communicating vessels of different sizes. Water level, spirit level. Water from reservoirs rising to tops of houses. Exception in case of very narrow tubes. Capillarity.
Floating power, or buoyancy of liquids.—Experiments on weight of water displaced by bodies immersed and by floating bodies. Principle of Archimedes.
Specific gravity.—Definition. Experimental determination (1) by catching and weighing displaced water; (2) by loss of weight in water.
Pressure of Air—
Experiments showing existence of atmospheric pressure [e.g., inverted jar of water, experiments with air-pump, suckers].
Barometer.—Construct by filling long tube with mercury. Show by passing barometer tube through cork of receiver that mercury falls when air withdrawn from above mercury in cistern, rises if air is let in.
Action of syringes. Pumps. Construction and working of air-pump.
Heat—