FoodNet

Elements of the theory and practice of cookery

1901

Page 18

Presented as published in 1901. Historical recipes may not meet modern food-safety standards. Cook from the modern interpretation, not the original instructions.
Suggestions for reading and home work in connection with this section. — Read in Early Chapters in Science about thermometers, pp. 241-24:4; and about the density of ice, pp. 250, 251. Try dis- tilling water and crystallizing alum according to directions on pp. 231 and 236. See what Dr. Prudden writes in his little book, Drinking-water and Ice Supplies, about *' The Earth's Stock of Water," pp. 12-15; "Kinds of Water," pp. 31-37; "Some Ways of Getting Water," pp. 78-89; and "Solid Water" pp. 115-125. This last chapter tells how ice is cut and stored. Section 4. Cleanliness and Cleaning All things of thee partake. Nothing can be so mean But with this tincture, For Th>j sake, It will be bright and clean. A servant by this clause Makes drudgery divine ; Who sweeps a room as by Thy laws, Makes that and the action fine. — George Herbert. 56. Pure air and pure water we have seen to be simply clean air and clean water. The importance of cleanliness is better understood than ever before, now that scientists have shown the close relation between dirt and disease. The dirt that shows most plainly may not be the most objectionable. A dusty chair is of much less consequence than an unclean dish-cloth. 57. Two kinds of dust: living and lifeless; bacteria. — The dirt in houses consists for the most part of dust, 32 THEORY AND PRACTICE OF COOKERY both alone and mixed with grease (fatty matter), mois- ture, and sticky substances. Dust is earth or other matter in particles so fine that it can he raised and carried hy the wind. Dust is everywhere present. We see how quickly it gathers on the floor and the furniture ; a sunbeam shows us that the air is full of it. This visible dust was for a long time the only kind known about. It has been discovered, however, that mixed with visi- ble dust is another kind, so fine that it can be seen only Fig. Two kinds of mould often found on food. with a microscope. This invisible dust is composed of tiny plants and their seeds, or spores. When these spores fall upon suitable material they grow. When enough plants are growing together they can be seen with the naked eye. 58- Experiments. — A. Expose a piece of bread or cheese, or some cooked fruit, to the air for a few days, covering it to keep it moist. What appears on the surface ? B. Examine this growth with a magnifying-glass or microscope. PREPARATORY LESSONS 33 Microscopic plants are of three kinds, moulds, yeasts, and bacteria (singular bacterium^ rarely used). They will be studied in other chapters. 59. Bacteria the most objectionable kind of dust. — Vis- ible dust may do harm by irritating the throat and lungs ; but certain kinds of bacteria, if they enter the body, may produce such diseases as consumption, diph- theria, and typhoid fever. Other kinds cause food to spoil. Bacteria thrive best in dark, damp places, where other dirt is present. Anything that kills bacteria or hinders their growth is called a disinfectant. Natural Aids to Cleanness