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Non minus immensa est bonitas tua, quæ patet omni
Quid tibi pro precibus, meritis et sanguine reddam,
At mihi deciduo cælestis spiritus adsis, Atque animam dono fragilem septemplice fulci, Quo minus, ob pronos in pristina crimina lapsus, Mc Pater iratus merito exaudire recuset,
Nec pro me precibus vellet certare Redemptor.
Tute animos animas, hominemque ad sidera tollis.
Conscius haud pridem sceleris, nunc inscius idem, 255
Æterni laudes totum resonante per orbem.
Christe, preces placeat geminatas fundere pro me.
Gloria in æternum, cœlo, terraque, TRIUNI.
PRODUCTION OF NATURE,
OBSERVED NEAR MONAGHAN, IN THE YEARS 1737-40.
PUBLISHED SOME TIME AFTER
TRANSACTIONS OF THE ROYAL SOCIETY.
In the beginning of May 1737, the warmest season that any body now alive remembers to have felt in Ireland, the cornel-trees, of which, in the plantations of Monaghan there were about a hundred, appeared almost covered with small caterpillars, of a dirty green or mouse colour, for the greater part, though some, considerably larger than the rest, were yellow. These worms, were employed partly in feeding on the leaves of the cornel, which was their only food, and partly in crawling, with a very swift motion for a worm, over the bark of the tree. As they crawled, they left each a fine thread scarcely visible to the naked eye upon the bark. These threads being almost infinitely multiplied by the inconceivable numbers of worms employed in the work, formed a silken web, as white as snow, glossy, and strong beyond the proportion of its thickness. In this web, the threads are not interwoven, they only cohere by the glutinous quality of the matter from whence they are extracted. By the end of May there was not a leaf to be seen on any of the cornels, except a few reserved for a very curious purpose, which I shall mention presently; but the worms, in the room of the green clothing of which they had robbed these trees, gave them one of white, so entire that it covered the whole bark, from the ground to the points of the slenderest twigs, and of so pure and so glossy a colour, that the whole tree shewed in the sun, as if it were cased
in burnished silver. The web was so strong, that if one disengaged it from the tree near the root, one might have stripped it at one pull, from the trunk to the branches, and even the very twigs. As soon as the worms had covered all the cornel trees, they removed from thence, and covered all the ash, beech, lime, crab-tree, and weeds that stood near them, with the same, but a thinner kind of workmanship.
The reader may desire to know how they travelled from one tree to another. Many of them crawled along the ground, and over every thing in the way, still leaving a thread behind them, and dispatching part of their business, as they went towards a more convenient surface to finish the rest on. But I did really imagine, some of them took an easier and more ingenious way. I have found many of them hanging by their own threads from the highest and most extended branches of the cornel. While they were in this situation, a gentle puff of wind might, by exciting a pendulous motion, waft them to the next tree. This seems to be the method, by which those very minute spiders, whose threads are made visible by the drops of water adhering to them in a foggy morning, transport themselves from one bush to another, though destitute of wings, nay, and sometimes across roads and rivulets.
As these worms seemed neither then, nor afterward, to make use of these webs, thus left on the bark of the trees; I take it for granted, they only wrought them to rid themselves of that glutinous mass, out of which they were drawn, and which nature producing in greater quantities than were necessary for the wrapping and stowing the worm in its crysalis state, prompted the creature to work it off the best way it could. The method it took for this purpose was admirable. It fastened its thread to some little eminence on the bark; and choosing, for the greater convenience of crawling, that even surface, kept continually in a brisk motion, till its troublesome burden was discharged.. I was for awhile greatly at a loss for the reason of its removing from its native tree, and spinning abroad upon the neighbouring ones. But it is possible the web might have grown too bright for its eyes, or too smooth for its feet, before its whole burden was exhausted; and so it might for
this reason have been obliged to spin out the remainder elsewhere.
About the beginning of June, the worms retired to rest, and their manner of preparing for, and executing this, was very ingenious and curious. Some of them chose the under sides of the branches, where they spring from the trunk, that they might be the better defended from the water, which, in a shower, flowing down the bark of the tree, is parted by the branches, and sent off on each side. There they drew their threads across the angle made by the trunk and branch, and crossing those with other threads, in a great variety of directions, formed a strong tegument on the outside. Within this they laid themselves along among the threads, and rolling their bodies round, spun themselves into little hammocks of their own web, which being suspended by the transverse threads, they did not press each other in the least. That they might stow the closer, they lay parallel to each other, and in the nicest order imaginable. Others still more ingenious than these, fastened their threads to the edges of certain leaves, which, no doubt, they had saved from their stomachs for this purpose, and with that slender cordage pulling in the extremity of the leaves, drew them into a kind of purse, in the inside of which they formed the same kind of work, and laid themselves up in the same manner as above. By this method they saved themselves a labour, which the rest were at the expense of, for the leaf served them very well for an outward defence against the weather.
These worms laid themselves up in their chrysalis state, in great numbers together, probably because they might help to keep each other warm, while nature was preparing for the great change, or in order to confine some subtile vapour issuing from their bodies, which was necessary to their reviviscence, and which had been easily dissipated had they not lain close together, and caught it from one another.
Between the worm thus laid up, and the hammock in which it was enclosed, a tough and pliant shell of a dark brown colour was found. This I take to have been formed by the perspiration, or some other cutaneous effluvia issuing from the worm, which, being stopped by the close tex