In 1876, The School Board For London commissioned W B Tegetmeier to produce " a scholars' handbook on the general principles on which the processes of Cookery and the sanitary management of a home depend". It was to be " a book fit for use in schools, where the pupils should be instructed in the first principles" of home management. It was found that by using it in the schools "The girls, in three months, can be taught plain cooking, washing, and cleaning, enough to prepare them for service, or to make them useful to their mothers at home." The book presents in great detail the minutiae of life in the Victorian home. In this abstract the pupils are instructed in the qualities of air and proper ventilation. It provides a fascinating glimpse into this aspect of the lifestyles of the time.
The Air we breathe is necessary to purify the blood and to support life. Air, though invisible, is a material substance, a quantity of it in a bladder or airtight bag prevents the sides being pressed together; it also possesses weight; a box, each side of which is one foot square (or one cubic foot), contains one ounce and a quarter of air. The air in a room twelve feet square and eight feet in height weighs ninety pounds.
Air is not a simple substance, but a mixture of several gases. The most important of these is oxygen, which forms one-fifth part of its bulk. It is the oxygen which purifies the blood when we breathe, and it also enables combustible substances to burn when set on fire. The remaining four-fifths of the air consist chiefly of nitrogen, which serves to dilute the oxygen and render it milder, otherwise both our breathing and the burning of fires would go on too rapidly.
The breathing of men and animals and the burning of fuel take away part of the oxygen of the air, and its place is supplied by a gas called carbonic acid. This is very injurious if breathed. Air containing only one-thousandth part (1/1000) of carbonic acid destroys health if breathed for any length of time. In crowded places, or in bed or sitting-rooms when the doors and windows have been kept closed for some time after they have been occupied, the air often contains two or three times as much of this poisonous gas, or from two to three parts in a thousand. If this air is breathed for any length of time it speedily causes headache, weariness, and loss of strength. Persons who spend great part of their lives in rooms filled with bad air become pale and sickly, and are liable to many more diseases than those living in pure air.
The air always contains a considerable quantity of moisture, which varies very much at different times of the year and in different places. When the quantity of moisture is so great that it settles upon objects and makes them damp, it is injurious to health; and houses in which the walls and foundations are damp are always unhealthy.
A large quantity of moisture passes away from the lady in the air that is breathed out from the lungs, and a great amount is produced by the burning of gas and other lamps.
Not only is the air of close rooms and houses rendered injurious by the carbonic acid and water produced, but it is made still more poisonous by the decaying animal matter which passes off in our breath, and which is also given out by the walls and floors of unclean houses, by dirty clothes, and by that air which comes into the house through drains or passes over stinking dust-bins and heaps of decaying refuse.
Whenever a house smells close and fusty to a person coming in out of the open air, it is always unhealthy, and sooner or later will produce illness in those who live in it. The good health that persons who live in houses in open country places enjoy is entirely owing to the pure air they breathe. But even in country villages the air is often rendered unwholesome by cesspools or dung-heaps being kept close to the house, or by the filthy habit of throwing the house-slops and dirty water on the ground close to the door.
A full-grown person takes into his lungs about two-thirds (2/3) of a pint of air every time he breathes, and when not breathing quickly, from running or hard work, he usually does so about eighteen times every minute; this is equal to twelve cubic feet every hour. This quantity of air weighs nearly one pound, so that we actually take into our lungs nearly twenty-four pounds of air every day, a greater weight than our food and drink taken together.
The air that passes out of our lungs is quite unfit to support life if breathed again, even when mixed with ten times its bulk of pure air, therefore the air in our living and sleeping rooms must be constantly changed, or it would soon become poisonous. Persons have often been killed by being shut up in close rooms or in ships during storms. The burning of a candle renders the air nearly as impure as the breathing of a single person, and every gas burner consumes a very much larger quantity.
The impure air that passes off from our bodies and that produced by the burning of lamps and fires, is always, from being heated, lighter than before, it therefore rises and at first collects in the upper part of the room, unless it is allowed to escape.
In a room that has a fire-place a stream of air is usually passing up the chimney, fresh air coming in by the cracks round the doors and windows. No bedroom should be slept in without a fire-place unless ventilation is otherwise provided for; even the quantity of air coming in round the window and door is not sufficient, it is therefore much better to sleep with the window open. This may be done without causing a draught, by placing a board three inches wide on its edge under the lower sash, which is thus raised, causing a space between the two sashes in the centre of the window; through this the air enters and being directed upwards does not cause a draught.
It is much more desirable to let the air come into a bedroom through the window than through the door, as the house being closed at night the air often come through the drains or damp cellars, and is not as pure as that which comes from outside the house. Gas is not desirable in close sitting or bedrooms, its effect on the air being much more injurious than candles or lamps.
Note: Tegetmeier's complete text can be viewed on-line in the Victorian Dictionary.