Google Translate does a half decent job.
For example, the beginning
Constare animalium corpora ex calidi, frigidi, sicci, humidique mixtura, nec esse horum omnium parem in temperatura portionem, demonstratum antiquis abunde est, tum philosophorum, tum medicorum praecipuis. Diximus autem & nos de iis, ea quae probabilia sunt uisa alio opere. In quo de iis, quae Hyppocrates constituit elementis, egimus. Hoc opere, quod illi proxime succedit, omnium temperamentorum differentias, quot hae, qualesque sint, siue generatim quis, siue membratim diuidat, inuenire docebo. Sumamque ab ipsa nominum interpretatione principium. Cum nanque ex calidi, frigidi, sicci, & humidi, temperatura conflari corpora dicunt, de iis, quae summo gradu sic se habent, ipsis scilicet elementis, aÃre, igni, aqua. terra, intelligendum aiunt. Cum uero animal, stirpemue calidam, humimidam, frigidam, uel siccam esse, non item. Neque enim ullum animal, aut calidum in summo esse posse, ut est ignis, aut in summo humidum, sicut est aqua: pari modo nec frigidum, siccumue in summo. Sed ab eo quod in mixtura pollet, appellationem sortiri,
The animal is composed bodies to be of hot, cold, dry, and moist mixture , nor the being of those of all the peer in the portion of the temperature has been demonstrated of old time, it is quite enough , as well as of the philosophers , as well as the principal of physicians . But we have said & which we find out what those are things that are more or less probable it seemed appropriate for another work . In which of the things which constitutes the elements of Hippocrates , and have dealt wickedly . This work , which is now the former is succeeded by , of all the combinations of the differences, and how many these are , and what they are , or in general any man , whether in its constituent parts divide , find the symptoms. Sumamque of names from the very interpretation of the principle. Since, for a portion of hot, cold, dry, and somewhat moist , the temperature of melting down their bodies , they say, of the things which the highest degree of the same relationship holds present, namely, the elements, air , fire, water . land , they understood . But when an animal, stirpemue hot , humimidam , cold water , or dry to be, not the same. For it is not any kind of animal , or the hot to be in the highest degree to be able to , as it is a fire , or at the top of the moist , as it is in water, and in the same way nor cold, siccumue at the top. But from the fact that in a mixture is endowed with , and the calling to draw lots
(stirpemue can become two words, stirpe mue, and humimdam can be corrected based on the proofreader's note to humidam) Which seems good enough to understand what he meant. A professional translation would be nicer, but probably too expensive. I have asked for a ball park quote, we'll see where that goes.