The first account the Royal Society received of the surprizing properties of the hydra, was in a letter from M. Buffon, dated the 18th of July, 1741, to Martin Folkes, Esq. their president, acquainting them with the discovery of a small insect called a polypus, which is found sticking about the common duck weed, and which, being cut in two, puts forth from the upper part a tail, and from the lower end a head, so as to become two animals instead of one. If it be cut into three parts, the middlemost puts out from one end a head, and from the other a tail, so as to become three distinct animals, all living like the first, and performing the various offices of their species: which observations are, adds Buffon, well averred.
There is no phænomenon in all natural history more astonishing than this, that man, at pleasure, should have a kind of creative power, and out of one life make two, each completely formed with all its apparatus and functions, its perceptions and powers of motion and self-preservation; and as complete in all respects as that from which they derived their existence, and equally enjoying the humble gratifications of their nature.[107]
[107] Goldsmith’s History of the Earth and Animated Nature.
Mr. Folkes, in confirmation of the foregoing article, communicated to the Society a letter from the Hon. W. Bentinck, Esq. at the Hague, dated September, describing the insects discovered by Trembley, adding, that he himself had seen them. In November, a letter was read from Dr. Gronovius, of Leyden, giving an account of a water insect not yet known to, or described by any author; after describing it, he adds, “but what is more surprizing, if this animal is cut into five or six pieces, in a few hours there will be as many animals, exactly similar to their parent.” The accounts of this animal were so extraordinary, that they were not credited until Professors Albinus and Musschenbroeck were provided with some specimens, and found all that had been related thereof to be exactly true.
November 25, a letter from Cambridge was read to the Royal Society, in which the author endeavours to lessen, by reason, the prejudices which then combated the belief of these facts. “Some of our friends,” says the author, “who are firmly attached to the general metaphysical notions they have formerly learned, reason strongly against the possibility of such a fact: but I have myself owned on other occasions, my distrust of the truth, or certainty at least, of some of those principles, and I shall make no scruple of acknowledging, that I have already seen so many strange things in nature, that I am become very diffident of all general assertions, and very cautious in affirming what may or may not possibly be. The most common operations both of the animal and vegetable world, are all in themselves astonishing, and nothing but daily experience and constant observation can make us see without amazement an animal bring forth another of the same kind, or a tree blossom and bear leaves and fruit.
“The same observation and experience make it also familiar to us, that, besides the first way of propagating vegetables from their respective fruit and seed, they are also propagated from cuttings, and every one knows that a twig of a willow particularly, cut off and only stuck into the ground, does presently take root and grow, and become as real and perfect a tree as the original one from which it was taken. Here then we find in the vegetable kingdom quite common, the very thing of which we have an example before us in the animal kingdom, in this new-discovered insect. The best philosophers have long observed strong analogies between these two classes of beings; and the more they have penetrated into nature, the more they have extended this analogy: now in such a scale, who is the man that will be bold to say, just here animal life entirely ends, and here vegetable life begins? or, just so far, and no farther, one sort of operation goes; and just here another sort, quite different, takes its place? or again, who will venture to say, life in every animal is a thing absolutely different from that which we dignify by the same name in every vegetable?” Thus does the author endeavour to persuade the prejudiced, and lead them to pay attention to the facts which were now laid open to their view, and which were further confirmed by a letter from M. Trembley, in January 1740; which letter was strengthened by an extract from the preface to the sixth volume of Reaumur’s history of insects. In March, 1742, Mr. Folkes gave an account of them to the Royal Society, from observations made on several polypes which had been sent by M. Trembley from Holland to him. The insects now began to be known, and were soon found in England, and the experiments that had been made on them abroad were published by Mr. Folkes,[108] my father,[109] and Mr. Baker:[110] conviction now became too strong for argument, and metaphysical objections gave way to facts. The animal is described in the following manner:
HYDRA.[111]
Flos: os terminale, cinctum cirris setaceis. Stirps vaga, gelatinosa, uniflora, basi se affigens.[112]
[108] Philosophical Transactions.
[109] Micrographia Illustrata.