can hence see the reason why many of the serpent tribe should convert a wholesome nutriment into a venomous secretion; why.the euphorbia, or spurge, so noxious to man, and most quadrupeds, should be greedily devoured by several of the insect tribes ; why the cicuta, which proves poison to the human race and the horse, should be luxuriously feasted upon by goats and quails,while the horse, on the contrary, feeds with plea sure on the aconite, or bane-berry, which the goat will not touch.
A thousand such peculiarities might be advanced, if it were necessary ; but these alone are prove, that every created substance possesses the basis of a nutriment for some order of animals or other : and that all that seems necessary, with respect to those generally esteem ed the most poisonous, is a peculiar power in the stomach to select the parts that are nutritious from those that are baneful, and to secrete these alone into the system.
These observations apply to food gene rally. We now proceed to observe, that even the same foods, under certain states of the stomach, to which they are natu rally appropriate, will notuniversally pro duce the same beneficial results. Two questions, hence, naturally arise. What are those states of the stomach, in which its appropriate foods have for the most part a tendency to prove injurious instead of salutary (for the digestion of every ali ment must do either the one or the other) ? And of what nature are those substances, which, under almost every circumstance, form an exception to the rule of disease, and may still be swallowed ed with benefit ? It is clear then, in the first place, that the states of the stomach here referred to are morbid states morbid either from idiopathic, or symptomatit affection : and secondly, that as in all such cases the common action of the stomach must be debilitated, and consequently its secreted or gastric juice-partake of the debility, or be extruded in a much weaker and more dilute state, those aliments only can be usefully employed, which are both capa ble of being digested with a small por tion of gastric energy, and at the same time capable, when digested, of affording a very large portion of the nutritive prin ciple.
It also happens, and that not unfre frequently, that in the preparation of such foods, we can add such accessary quali ties as may tend to oppose the morbid af fection of the stomach, or the tempera ment generally, and thus acquire a dou ble advantage, by imprinting upon our aliment a medicinal character as when in flatulencies we make spices a part of the regimen recommended ; in scorbutic affections, acids ; and in acidities, ani mal oils. But such accessaries are ra ther medicines themselves than foods, and have scarcely a right to be regarded otherwise.
What then are those states of the sto mach, either original, or dependent, which render it necessary to deviate from the general license of nature, and to restrict those who are thus morbidly affected to medicinal diets or regimens ? To catalogue am) treat individually of the whole of these would require the space of a quarto volume : we must con fine ourselves therefore to the grief of such affections, and, in discussing these few, endeavour to make our rules so :omprehensive, as to be a general direc tory to the rest.
The principal diseases then, whether local or constitutional, in which the hu man stomach becomes so affected as to render it a proper subject of medicinal diet, are, acidity, flatulency, heart-burn ; impletion; chronical sick-head-ache and hypochondriasis ; hepatic affection from hot climates ; hepatic affection from hard drinking.