2. A larder must be cool. If it have no rooms above it, the roof must be so constructed as to keep out the heat of the sun. It is essential that its windows and ventilators should face the north. The temperature which is most favourable for the growth of microbes is one which approaches to blood-heat, and, speaking generally, one may say that the higher the temperature, the more likely is the 'cultivation' of microbes to go forward. It is important that the flue of the kitchen fire, or any other flue, should not touch the wall of the larder.
3. Good ventilation is essential. The windows should be big, and should be protected on the outside with wire gauze, so as to prevent the access of flies or other insects.
4. On no account must there be a gully communicating with any underground drain or sewer either inside or, indeed, near to any place where food is stored. In short, we must bear in mind that sewer-poisoning may be indirect through the food, as well as direct from the sewer itself. When the shelves and floor of a larder are washed, they should be wiped dry, and such washing should be carried out in dry weather, so that the drying process may be complete.
We all know how sensitive food is to unwholesome contaminations, and one may well have a doubt as to the sanitary condition of show dairies, where a cool, plashing fountain plays in the centre, because such fountain must have a waste-pipe, and one must fear that such waste-pipe communicates with a drain. A dairy, equally with a larder, should be kept cool and dry, and should offer no facilities for the ingress of putrefactive products from a sewer.
I have already pointed out that it is no protection to have waste-pipes trapped, because in every form of trap one must have stagnation, and wherever stagnation occurs there must be putrefaction. A very small quantity of food-refuse or milk is enough to set up putrefaction in a trap. If any outlet for water is thought desirable in a larder, it should be in the form of an open gutter which can be thoroughly cleaned and dried, and which should pass directly through the wall on the floor-level, the opening in the wall to be closed by a sliding trap-door when the gutter is not being used. No bacteriologist needs to be reminded that a water-trap is necessarily a cultivating chamber.
CHAPTER II
THE SANITATION OF THE ISOLATED DWELLING
We are now in a position to consider the sanitation of the isolated dwelling. Having dwelt upon the evils of putrefaction, it is to be expected that methods which involve no putrefaction will be recommended. Further, it must be remembered that there are many situations which are otherwise suitable for a dwelling, but are rendered unsuitable by the lack of water; and in these days we have become so absolutely dependent upon water, that no site for a dwelling where water is scarce is acceptable.