Atmospheric pressure at various heights.

SOUND.
Velocity of sound = (feet per second)
Air = 1086
Water = 4900
Wood = 11,000 to 17,000
Rock = 1,900 to 2,200
Granite = 1,665
Iron = 17,500
Copper = 10,300

Human voice can be heard at 150 yards.
Rifle at 5,500 yds.
Cannon 33,000 yds.
Large guns, up to 100 miles has been known.

(Certain tribes used to communicate by
whistling and could exchange messages over distances of around 10 miles.)

WATER.
Head in feet x 0.4325 = lbs. / sq. in.
Pressure of 1 lb. / sq. in. = column of water 2 ft 3¾" high.

Depth in fathoms x 2.6624 = lbs. / sq. in.
1 inch of rainfall x 100 = tons per acre.
1 inch of rainfall x 14.46 = millions of gallons / sq. mile

1 inch of snow = 0.433 lb. per sq. ft.
1 cubic foot of snow weighs 5.2 lbs. (average).

A wave 20 to 30 feet high can exert a force of 1 ton per sq. ft.
The maximum force of wave observed at Skerryvore = 3 tons per sq. ft.

1 gallon of water = 10 lbs.
1 cu. ft. of water = 62.37 lbs. = approx. 1000 ozs.
Cubic ft. per minute x 9000 = gallons per day.

Water lost to evaporation on UK canals = 0.8" per yard of canal. Per day  (= approx. 0.27 cu ft). [ I believe this is for narrow canals.]

AIR.
1 gas mantle consumes 6.7 cu.ft of air per hour.

The heat from burning 1 cu. ft. of gas will remove 3,000 cu. ft. of air per hour, and in this way is used to ventilate mines.

A chimney for a steam engine should be:
Base = height / 10 if round; base = height / 11 if octagonal; base = height / 12 if circular.
The greater the height, the more draught produced.
Height = (0.3HP / A) squared. Where A = area of chimney in square feet, HP = Horsepower of boiler.

AIRCRAFT.

Pulse jet (real name Athodyd = Aero-Thermo-Dynamic-Duct), as used in WW2 V1, a model 22 ins long built in 1957-8 generated 4lbs thrust, and gave a top speed of 85 mph.

First steam powered aeroplane was built in 1848.
Maxim (the designer of the eponymous gun) built a very large steam-powered aeroplane weighing nearly 4 tons, a few years later. (He also tried steam powered guns, and designed fairground machinery.)

A 5c.c Miles Special diesel engine will produce almost 0.5 b.h.p.
(that is the model aircraft compression-ignition engine, not a "true" diesel.)

A good fuel for model diesel engines is: 30% ether, 30% paraffin (kerosene); 17% DERV (road diesel); 20% castor oil; 3% amyl nitrate. The amyl nitrate can be replaced with nitrobenzene.
(And we used to buy all of these and mix it ourselves.)

There have been many experiments with steam powered aircraft and there is a small number of enthusiasts that build models of them today. (Searches in GOOGLE will find many references, and one site can be found on the LINKS page.)

There are many designs available for home-built aircraft engines of all types.

FUELS.
Early internal combustion engines used a range of fuels.
Benz cars, among others, used Benzene, and some of the early engines used naptha.

If you are restoring an antique engine, or building a replica of one, or even a very early model, it is worth checking what it should have used.
I understand that naptha was a common fuel around 100 years ago, particularly with smaller engines.
( Naptha (and benzene) are both far more volatile than petrol. )

In one case, a model would not run on petrol, but ran perfectly when given a good drink of naptha, the fuel for which it was originally designed.

In small quantities naptha is what is commonly called "petrol", as used in petrol cigarette lighters.
( Or, to be precise, I have not confirmed that this is actually naptha, but it certainly acts in the same way and will do the job! )

(Thanks to Dick Guys

LIGHTING.
The following is interesting as it originated from a railway company. (Not sure why "cinema" is in there though.) It shows how little light  was normal compared to today.

The following levels of illumination in buildings are suggested. Figures in foot-candles (1 foot-candle = 10.7 lux.)