of a particular sort and falling in certain places; from the transformation of horse-hairs, and from electrical disturbances. A reverend bishop once communicated to the Royal Society a contribution on the subject of the origin of eels which in substance averred that he had seen young eels on the thatching of a cottage and that the eggs were adhering to the reeds of the thatching before they were cut, and were finally hatched on the roof by the heat of the sun. Helmont, an ancient writer, is specific and gives a recipe for producing eels. Two pieces of turf with May dew upon them were to be taken and the grassy sides apposed and placed in the sun. After a few hours an 'infinite quantity of eels' were generated. Helmont doubtless felt so sure of this that he regarded trying it a superfluous inconvenience, having no use for young eels. In the 'Piscatory Eclogues' is a reference in the same strain:
Say, canst thou tell how worms of moisture breed,
Or pike are gendered of the pickrel weed?
How carp without the parent seed renew
Or slimy eels are formed of genial dew?
Aristotle wrote: 'The eel is neither male nor female and is procreated from nothing.' He explained that they were produced from the slime of their bodies, which they scraped off against the pebbles or stones or by contact with each other in their sinuous migrations. This sounds fishy to the twentieth century, but it is easy to see that to Aristotle there should be something in it. There was the slime—that was evident enough. It was purposive in amount, it gave the slipperiness to a creature which is notoriously slippery. The remarkable abundance of eels required a theory of reproduction on a grand scale. And as for their rubbing together, a mass of wriggling and intertwining eels, the well-known 'eel-ball,' suggested nothing more strongly. What more simple and, for those times, natural!
Now there is a curious mixture of stumbling truth and preposterous error in the development of the eel question from this time forward. There was another teaching concerning the source of eels. Some who examined them discovered many small worm-like creatures in their internal machinery and insisted that these were the young and were produced alive from the parent eel—that is, that the eel was viviparous. This was certainly a much more natural and credible explanation, but it was scorned by Aristotle and Aristotle was correct. He said they were not eels, but were worms, and modern observations sufficiently uphold him. Yet the contrary opinion was held by the scientists of the middle ages, and names which are written high and imperishably on the scroll of fame subscribed to it. Leeuwenhoek, the discoverer of bacteria, and the renowned Linnæus believed that eels were not spawned and hatched but were born.