250 OF FOOD AND THE DIGESTIVE PROCESS. 



of the purely Carnivorous animals is destitute of Sugar, consisting, like 

 their food, of proteine-compounds and fatty matter only. 



437. No fact in Dietetics is better established, than the impossibility 

 of long sustaining health, or even life, upon any single alimentary prin- 

 ciple. Neither pure albumen or fibrine, gelatine or gum, sugar or starch, 

 oil or fat, taken alone for any length of time, can serve for the due nu- 

 trition of the body. This is partly due, so far as the non-azotized com- 

 pounds are concerned, to their incapability of supplying the waste of the 

 albuminous tissues. This reason does not apply, however, to the pro- 

 teine-compounds ; which can not only serve for the reparation of the 

 body, but can also afford the carbon and hydrogen requisite for the sus- 

 tenance of its temperature. The real cause is to be found in the fact, 

 that the continued use of single alimentary substances excites such a 

 feeling of disgust, that the animals experimented on seem at last to 

 prefer starvation, rather than the ingestion of them. Consequently it 

 is quite impossible to ascertain, by such experiments, the nutritive power 

 of the different alimentary principles ; no animal being capable of sus- 

 taining life upon less than two of them at least. The same disgust is 

 experienced by Man, when too long confined to any article of diet, which 

 is very simple in its composition ; and a craving for change is then ex- 

 perienced, which the strongest will is scarcely able to resist. Thus, in 

 the treatment of Diabetes, a disease in which there is an undue tendency 

 to the production of sugar in the system, it is very important to abstain 

 completely from the introduction of saccharine or farinaceous matters 

 in the food ; but the craving for vegetable food, which is experienced 

 when the diet has long consisted of meat alone, is such as to make per- 

 severance in the latter very difficult ; and a means has been latterly 

 devised of supplying this want without injury, by the use of bread from 

 which the starchy portion has been removed, the gluten or azotized 

 matter alone being eaten.* 



438. The organic compounds, which have been enumerated as sup- 

 plying the various wants of the system, would be totally useless without 

 the admixture of certain inorganic substances, which also form a con- 

 stituent part of the bodily frame, and which are constantly being voided 

 by the excretions, especially in the Urine. These substances have 

 various uses in the system. Thus common Salt, or the Chloride of 

 Sodium, appears to afford, by its decomposition, the muriatic acid which 

 is concerned in the digestive process, and the soda which is an important 

 constituent of the bile. Its presence in the serum of the blood, also, 

 and in the various animal fluids which are derived from this, probably 



* As an illustration of the advantage of this treatment, even in unpromising cases, 

 the author may cite an instance which has come under his own observation. The 

 patient was a man of 72 years of age ; the disease had lasted at least a year, and was 

 decidedly on the increase ; considerable loss of flesh and of muscular vigour had taken 

 place ; and the quantity of sugar in the urine was such as to make it quite sweet to the 

 taste. By the careful restriction of his diet to animal flesh and gluten-bread, this in- 

 dividual kept the disease in complete check for more than five years; he gained flesh, 

 and improved in strength ; and his urine lost its sweetness. Having two or three times 

 ventured upon a return to his ordinary diet, his old symptoms immediately manifested 

 themselves, warning him of the necessity of perseverance in the strict regimen pre- 

 scribed for him. He died at last, at the age of 77 years, of old age, rather than of any 

 specific disease. 



