Dr. Preston was evidently timid and fearful--foreboding ill--during the whole progress of his experiment. We think his story fully justifies this conclusion. In such circumstances, what could have been expected? There is no course of regimen in the world which will succeed happily in a state of mind like this. It should be carefully observed by the reader, that Dr. Preston speaks of entering upon a "severe course of diet;" and also, that, in attempting to give an opinion as to the best kind of vegetable food, he speaks of potatoes, prepared in a certain specified manner, as being preferable to any other. Now, I think it obvious, that Dr. Preston's "severe course" partook largely of _crude_ vegetables, instead of the richer and better farinaceous articles--as the various sorts of bread, rice, pulse, etc.--and, if so, it is not to be wondered at that it was so unsuccessful. In short, I do not think he made any thing like a fair experiment in vegetable diet. His testimony, therefore, though interesting, seems to be entitled to very little weight. This conclusion is stated with the more confidence, from the fact that some of the best medical writers, not only of ancient times, but of the present day, appear to entertain serious doubts in regard to the soundness of the popular opinion in favor of the "beef-steak-and-porter" system of curing scrofulous patients. Dr. Clark, in the progress of his "Treatise on Consumption," almost expresses a belief that a judicious vegetable diet is preferable even for the scrofulous. He would not, of course, recommend a diet of _crude_ vegetables, but one, rather, which would partake largely of farinaceous grains and fruits. Nor do I suppose he would, in every case, entirely exclude milk. Dr. Cheyne, in his writings, not only gives it as his opinion that a milk diet, long continued, or a milk and vegetable diet and mild mercurials, are the best means of curing scrofula; but he also says, expressly, that "in all countries where animal food and strong fermented liquors are too freely used, there is scarcely an individual that hath not scrofulous glands." A sad story to relate, or to read! But, Dr. Lambe, of London, and other British physicians, entertain similar sentiments; and Dr. Lambe practices medicine largely, while entertaining these sentiments. I could mention more than one distinguished physician, in Boston and elsewhere, who prescribes a vegetable and milk diet in scrofula.