The “Father of Medicine,” in denouncing its use (especially in pulmonary cases) was followed by nearly all medical writers, some of whom, however, were not slow, when otherwise differing from him, to assert that he killed more folk than he saved by his practice of leaving Nature to effect its cure. Paulus Jovius sums up historically the medical attitude towards Eels: “abhorred in all places and at all times, all physicians do detest them, especially about the solstice.” As Galen’s dictum[709] that fish afford the most desirable food for “the idle, the old, the sick, and the silly” embraces the majority—if we allow Carlyle’s “mostly fools”—of mankind, it would be idle to pursue the dietetic side, were it not for the _distinguos_ (to use the old Schoolman’s term) as to which fishes fell within or without the Mysian’s category. Diphilus (with Philotimus and others) speaks disparagingly of some, but highly recommends others. _Habitat_ alone, he urged, formed the deciding line between the clean and unclean. His _Treatise on Food for the Well and Ill_[710] divides sea-fish into (A) those which keep near the rocks—these, in his words, “are easily digested, juicy, purgative, light, but not very nutritious”—and (B) those which haunt deep water—these are “much less digestible, very nutritious, but upsetting to the internal economy.” Alexander Aphrodisiensis attributes the superiority of Class A to the fact that, as the water round the rocks is in perpetual motion, its denizens continuously exercise themselves.[711] Galen, for a somewhat similar reason, appraises as the lowest in nutriment the inhabitants of marshes, lakes, and muddy waters, because of their lack of swimming exercise and their impure food. A further subdivision commends itself to Rhazes. All fishes rough of scale, mucilaginous and white-coloured are best; those of a black and red shade must be avoided.[712] A special _distinguo_ extends to the part of fish, as Xenocrates plumps for the tails, on account of their being most exercised! Bonsuetus, centuries after Galen, echoes him: “All fish that standing pools and lakes frequent Do ever yield bad juyce and nourishment.”[713] But however divided the ancient practitioners were in their estimate of the digestibility of a fish diet, or of particular fishes, in their ichthyic remedies internal or external they credulously and enthusiastically coincided. Hence rained piscine prescriptions in every form, fresh, salt, cooked, calcined: every part and tissue, flesh, bones, skin, trail, brains, gills, _viscera_, and teeth—each and all were regarded as specifics against some human disease or infirmity.[714] All ailments practically find a cure in the ichthyic panaceas or nostrums which render old medical tomes boresome from repetition, and yet at times diverting. In regular prescriptions and old wife recipes alike, fish play a prominent part.