The answer is that no class in Great Britain lives on bread exclusively. Bread appears from the government statistics already quoted to form only about half the diet of the workers of the country. Their diet includes also some milk, meat, and vegetables, and such substances, according to Dr Hopkins’ experiments, certainly contain the substance, whatever it may be, that is missing from the artificial diet on which his young rats failed to thrive.
One last point. It will have been noticed in the figures given above that the variations in protein content, digestibility, and energy-value, between different kinds of bread are usually not very large. There is, however, one constituent of all breads whose proportions vary far more widely, namely water. During last summer the author purchased many samples of bread in and around Cambridge, and determined the percentage of water in each sample. The samples were all one day old so that they are comparable with one another. The results on the whole are a little low, probably because the work was done during a spell of rather dry weather, when the loaves would lose water rapidly.
The average figures are summarised below:
| Percentage of water | |
|---|---|
| Cottage loaves made of white flour | 31·7 |
| Tinned loaves made of white flour | 32·7 |
| Small fancy loaves made of white flour | 33·7 |
| Tinned loaves made of “Standard” flour | 35·9 |
| Tinned loaves made of brown or germ flour | 40·0 |
The figures speak for themselves. There must obviously be more actual food in a cottage loaf of white flour containing under 32 per cent. of water than in any kind of Standard or brown loaf in which the percentage of water is 36 to 40. It is quite extraordinary that no one who has organised any of the numerous bread campaigns in the press appears to have laid hold of the enormous variation in the water content of different kinds of bread, and its obvious bearing on their food-value.
BIBLIOGRAPHY
The reader who wishes further information on any of the numerous subjects connected with the growth, manipulation and composition of breadstuffs is referred to the following publications, to which among others the author is much indebted. The list is arranged, as far as possible, in the same order as the chapters of the book.
CHAPTER I.
The Book of the Rothamsted Experiments, by A. D. Hall. (John Murray, 1905.)
The Feeding of Crops and Stock, by A. D. Hall. (John Murray, 1911.)
Fertilizers and Manures, by A. D. Hall. (John Murray, 1909.)
The Soil, by A. D. Hall. (John Murray, 1908.)
Agriculture and Soils of Kent, Surrey, and Sussex, by A. D. Hall and E. J. Russell. (Board of Agriculture and Fisheries.)
Some Characteristics of the Western Prairie Soils of Canada, by Frank T. Shutt. (Journal of Agricultural Science, Vol. III, p. 335.)
Dry Farming: its Principles and Practice, by Wm Macdonald. (T. Werner Laurie.)
Profitable Clay Farming, by John Prout. (1881.)
Continuous Corn Growing, by W. A. Prout and J. Augustus Voelcker. (Journal of the Royal Agricultural Society of England, 1905.)