But, granting even the most that the friends of animal food can claim, what would the case of Dr. Preston prove? That the healthy are ever injured by the vegetable system? By no means. That the sickly would generally be? Certainly not. Dr. Preston himself even specifies one disease, in which he thinks a vegetable diet would be useful. What, then, is the bearing of _this single and singular case_? Why, at the most, it only shows that there are some forms of dyspepsia which require animal food. Dr. Preston does not produce a single fact unfavorable to a diet exclusively vegetable for the healthy.[4] It is also worthy of particular notice, that not a fact is brought, or an experiment related, in a list of from thirty to forty cases, reported too by medical men, which goes to prove that any injury has arisen to the healthy, from laying aside the use of animal food. This kind of information, though not the principal thing, was at least a secondary object with Dr. North; as we see by his questions, which were intended to be put to those who had excluded animal food from their diet for a year or more. But, let us take a general view of the replies to the inquiries of Dr. North. The sum of his first three questions, was,--What were the effects of excluding animal food from your diet on your bodily strength, your mental faculties, and your appetite and animal spirits? The answers to the three questions, of which this is the same, are, as will be seen, remarkable. In almost every instance the reply indicates that bodily and mental labor was endured with less fatigue than before, and that an increased activity of mind and body was accompanied with increased cheerfulness and animal enjoyment. In nearly every instance, strength of body was actually increased; especially after the first month. A result so uniformly in favor of the vegetable system is certainly more than could have been expected. One physician who made the experiment, indeed, says, that though his mind was clearer than before, he could not endure, so long, a laborious investigation. Another individual says, he perceived no difference in this respect. A third says, she found her bodily strength and powers of investigation somewhat diminished, though her disease was removed. With these exceptions, the testimony on this point is, as I have already said, most decidedly--I might say most overwhelmingly--in favor of the disuse of animal food.