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A CURIOUS ACCOUNT OF THE SILK WORM. From the Tranfactions of the Society of Arts, Vol. II.
LETTER I. FROM MRS. WILLIAMS TO MR. MORE*.
Am infinitely obliged by your layAm infinitely obliged by your laying my letters before your truly munificent fociety; therefore, with the utmoft candour, acquaint you with my method of training my favourite reptiles. The fole reafon of my hatching them earlier than ufual was as follows: I put the papers with the eggs into a pidgeon hole in a cabinet, nearly oppofite to the fire. As foon as the froft fet in, I covered the hole with paper feveral times double, to keep out the night air; the event anfwered my moft fanguine wishes; they came according to expectation: the query was then, how to get food for my little family, the weather being cold and very fevere, and the lettuces that were to be got, were very small, and not enough to fuffice them: a thought immediately occurred, as the blackberry had a near affinity to the mulberry, why might they not ferve for food? As the tender part of the leaf appears filky, I tried them, they eat furprisingly, and grew amazingly. I muft here remark I had them gathered from the young fhoots, as their texture is moft delicate, and divefted them of their thorns without bruifing the leaves. My refearches, however, did not ftop here; I next prefented them with the young and tender leaves of the elm, which they devoured with great avidity. Cowflip leaves, and flowers, they are very fond of; and it is really curious to thofe who love to pry into the fecrets of nature, to fee how they will, when fatisfied, nestle into the pipes, and repofe themselves. From hence forward, I fed them promifcuously on all the aforefaid vegetables, together with primrofe leaves and flowers, until the mulberry leaves came; but when I once prefented LOND. MAG. Jan. 1785.
them with that food, adieu to all other, they would not touch it.
It is worthy remark, they will not touch a red flower; I tried them with rofes, polyanthus, fweet-williams, and pinks, and they feemed to avoid them with a kind of horror. I fuppofe nature,debars their feeding on them, as it might hurt the colour of the filk. I keep them in a woman's large hatbox, feed them every day at ten o'clock, at four in the afternoon, and eleven at night; keeping them very clean. When I clean them I remove them as follows: in a morning they are always upon the leaves, I take them out gently upon them, and when the box is cleared, I lay them in on the fame leaves, with frefh ones over them (with the dew on if I can get them) and the fibre fide of the leaves up: when they are all on the upper leaves, I remove the old ones; by this method a quantity of filk is faved, for, from the moment they are hatched, they move themfelves by a filken web; the filk continually iffuing from their mouths, if they crawl to any diftance: therefore, I do not approve of the method ufed here, of ftriking them with a feather off the leaves, to which they ftrongly adhere, as every time that practice is ufed, they not only lofe a quantity of filk, but are vifibly in pain, which may be seen by their various contortions; by thefe means, and keeping them dirty, they do not rear one tenth part of what they hatch, nor bring them to any fize, though at the appointed time they will fpin, but the filk is not worth mentioning.
And now for the indications of fpinning: when they have fhed the laft coat, or exuvia, in the aurelia ftate, it requires great attention to watch them,
Mrs. Williams of the Poft-Office, Gravefend. It feems almoft unneceffary to inform our Leaders, that Mr. More is the able and ingenious fecretary of the Society.
left they deceive you in regard to the filk. The firft indication of their being near fpinning is a transparency all over them, with a vifible circulation of the blood, or glutinous matter, which I humbly fuppofe forms the filk, and affifes in fpinning: this is vifibly feen circulating down the middle of the back. The next fign is, they erect themfelves on their bellies, with their heads in form of a fphinx, fometimes feeming to play, biting their fides and filken tail, then lying dormant: but the most certain criterion is, when they eat from fide to fide of the large fibres in a circular form, nibbling the leaves to atoms, and wafting them. At this period they become of a fleshy colour,
their backs appear very luminous, efpecially by candle light.
Laftly, they move themfelves in a circular manner from fide to fide of the box, at this moment they are to be put in papers, or all the labour will prove abortive. If you approve it, I ̊ shall fend my filk for your infpection.
Since I wrote the foregoing, a gentleman has been at my office, who lived. three years in Italy; he declared, though he had feen many thoufands fpin there, he never faw finer worms than mine, and expreffed his aftonifhment at their fpinning at this feafon. I am, Sir, Your much obliged humble fervant, A. WILLIAMS.
I Was favoured with your letter yesterday, and beg you to return my moft refpectful devoirs to your good Society for the honour they have conferred on me, in thanking me for my humble endeavours, in regard to thofe dear little innocent reptiles, the filk worms. I fhall fend my filk up next week by a friend, under three different claffes (viz.) that of my firft brood, that of my fecond, and fome reeled off the eighteenth, nineteenth, and twentieth of November.
I have even at this time moths laying eggs, and I dare fay not lefs than two hundred this evening, while I was looking at them; and I again aver, I could breed them, and produce filk worms from them, all the winter, had I a fpot of ground. Lettuce may be produced all the winter, fown on the north borders where the fun comes, and that in the most inclement feafons, only by, covering them at night with hay or ftraw, and removing it when the fun is out, as may primrofe leaves, and it muit be a hard winter, indeed, when there are no bramble leaves to be got, I am not clear whether I informed you I feed my worms with the leaves moift, as I have not time to take copies of the letters I write, but this I am clear in, they thrive "moft on them when fo. As to cocoons, I have none, for after my firft eflay of reeling off about
Gravefend, Dec. 5, 777. a dozen, I obferved that the filk, the nearer it came to the cocoons, grew finer, ftronger, and better coloured.. It immediately occurred, why might not the whole cocoon be reeled off.
As I obferved every minute circumftance of the worms fpinning, from the firft formation of the woof, and perceived it fpan from right to left, why, might not I, by following its paces, obtain all the filk it fpun: I tried the experiment in water, fo hot I could fcarce, keep my hand in, and it anfwered my moft fanguine wishes. The strong glutinous matter which forms the contexture of the cocoon immediately gave way, and I reeled off every fingle thread. It is to be obferved, I only ufed milk warm water in the firft procefs.
The first few cocoons (about a dozen) I made artificial flowers of, equal in texture to thofe of Italy; but I thought the real filk would be of more value, which is the fole reafon of my winding it all off. My chryfalis's I put in bran the moment they are wound off, and then watch them every day, until I fee the place where the moth is to eat out. I then lay them on white paper, where they foon make their appearance.
Í muft here obferve there are more males than females, the reafon I leave to be determined by judgements fuperior to mine; but this I know,
which is well worth the while of naturalifts to inveftigate, that the female aurelia is full of eggs before the changes her ftate to that of a chryfalis.
I am, Sir, with all refpect, your moit obedient fervant, A. WILLIAMS.
I believe I forgot to inform you of the experiments I made in regard to the dung of the filk worm: I put fome to fome auriculas almoft exhaufted, infomuch that there were nothing but their hearts left; in a few days they turned of a vivid green, put forth fresh leaves, and are now in the moft flourishing state; and will, I dare fay, blow about Christmas. I tried it on various different flowers, annuals as well as others; it anfwered equally the fame. As to the rapidity of enforcing vegetation, proofs pofitive carry conviction; and I will venture to affirm there is not an exotic, however delicate, but I could rear with this very dung, provided the fun fhone on them.
Poft-Office, Gravefend, Dec. 8, 1777.
As I was reeling one day, I mentioned my thoughts to a gentleman, who begged leave to look at my reel and method, and who I found to be principal phyfician to a fleet of tranfports going to join Lord Howe; he failed; I told him I was certain it was fo, and the first time I cut myself I would try its efficacy; accordingly, next day, in mending a pen, I cut my thumb to the bone, and through part of the nail; it bled profufely; I tried my ftiptic, bound up the wound; the hemorrhage ftopped, and the wound healed in three days. Since which I have tried it on feveral, and it always had the desired effect. I really and fincerely believe, that half the benefit arifing from this minute part of the grand Creator's works are not yet unravelled, thofe which are ferve to elucidate the infcrutable ways of the omnipotent Creator of the univerfe, whofe works I shall ever adore with reverential awe and wonder. I am, Sir,
Your most obedient fervant,
HISTORICAL ACCOUNT OF PROPAGATING THE SILK WORM, AND MAKING SILK IN ENGLAND.
In a Letter from the Honourable DAINES BARRINGTON to Mr. MORE. DEAR SIR,
Firft then, with relation to the encouragement intended to the produce of filk in England, which hath not as yet indeed fucceeded, but which is certainly a moft capital object, as it affords
employment for women and children. The filk worm feems to be originally of Afia, but not of the most fouthern, or even tropical climates of that part of the globe. Both extreme heat and thunder ftorms are faid to be very prejudicial to this infect+.
It was first introduced into Sicily and Calabria in the thirteenth century; and into France, by Henry IV. who began the trial in Languedoc‡; and which answered fo well, that James I. made G 2
*The greatest quantity of the Chinese filk is made in the neighbourhood of Nanquin, which is
in the 324 degree of N. latitude. + Malphigi de Bombyce.
Raw filk is now produced in many of the northern provinces, particularly the Ile de France.
the fame laudable attempt in England. This King, therefore, iffued a proclamation in the fixth year of his reign for the encouragement of planting mulberries *-holding forth the example of France, and directing it to be read at the quarter feflions. As the introduction of fuch new culture muft neceffarily require every fort of protection for a confiderable number of years, it is not extraordinary that it fhould not have been then established on account of the turbulency in the latter part of James's reign, and the greater troubles in that of his fucceffort. The propofal having, therefore, not at this time fucceeded, by no means furnishes a conclufive proof against its practicability; but, on the contrary, it is evinced by the before-mentioned proclamation, that both the King and his privy-council conceived it might be carried into execution. Affuming it, therefore, that the attempt is not defperate, it may be material to point out a few circumftances which may require attention, fhould the Society ever think it proper to continue or renew their miums on this head.
The first requifite is the raifing a proper number of mulberry trees, and it is generally fuppofed that the leaves of the white mulberry are better food
for the infect than those of the red.
Mr. Swinburn, however, who lately travelled through Calabria, informs us, that the red mulberry is there preferred, because the leaves do not appear till ten days or a fortnight after thofe of the white mulberry, which is, therefore, much more liable to be hurt by the early frofts of the fpring, even in that more
It may not perhaps be inexpedient alfo, that a premium fhould be given to the perfon who may difcover what other food may be fubftituted instead of mulberry leaves. I take it upon my memory (though I cannot at prefent
refer to my authority) that lettuce hath anfwered well for this purpofe; and mulberry leaves fhould not be folely relied upon, even if they are the best food for filk worms, because they may be blighted in a bad season.
If contrary, however, to the opinion of the Calabrians and Perfians, white mulberry fhould be deemed more proper, I have often been informed that there is a large tree of this kind in the Bishop of London's garden at Fulham, and which was probably introduced by Bishop Compton, during the reign of Charles II.
As perhaps more filk is produced in China than in every other part of the globe, we fhould as near as may be conform to their ufages, both in raising the proper food, as alfo in breeding this valuable infect, especially as fuch ufages have had the fanction of many centuries.
The chief mart for the raw material is in the neighbourhood of Nanquin, which is fituated in the thirty-fecond degree of N. latitude. But in that more fouthern climate, they hatch the infect in rooms heated by ftoves, and from which particular care is taken to exclude both mice and rats. Halde alfo informs us, that when the infect is very young, it is much difturbed by the barking of a dog, or crowing of a cock, which inconveniences they will probably experience in moft parts of England, where there may be attempts to rear the filk
See the Harleian Mifcellany, Vol. II. p. 203. This project, however, was not totally neglected by Charles I. for in 1628, he appointed Waiter Lord Afton to be keeper of the garden, mulberry trees, and filk worms, near St. James's. See Romer's Fæd. A. D. 1628.
See alfo Mr. Scot's additional volumes to Chambers's Dictionary, where it is faid that the Perhaps ule the black mulberry. As for the white, affording the chief tood to filk worms in China, it is beloved that diey have not the black mulberry in China.
In history of China.
I have fcarcely any doubts with regard to its being true.
London is chiefly fupplied with lobfters, either from the coaft of Norway or the Orkneys; nor do fhips fail from either, till their cargo of thefe fifh is nearly completed. If in the courfe of the voyage, however, the veffels happen to be near a great gun, when it is fired, the greater part of the lobfters Thoot their claws, and a difh of their lading is fometimes extorted by the threat of a falute.
With regard to the discovering a fuccedaneum for mulberry leaves, the following circumftances may perhaps deferve attention:
The field for experiment is a very wide one, and, therefore, the firft attempt fhould be made with trees as nearly fimilar as poffible to the mulberry, both in texture of the leaf, as alfo in the taste of it.
But we have perhaps a more unerring guide in thefe refearches than our fenfes.
Moft infects prefer the leaf of fome particular tree or plant, but not exclufively fo. If, therefore, the infects which feed upon the mulberry in England are alfo found upon other trees or plants, this will afford the ftrongeft prefumption that they resemble each other in their flavour and nutritive qualities.
From the reafons which I have here fuggefted, I have at least convinced myfelf that the attempt to produce raw filk in England is by no means defperate, and to give it the better chance of fucceeding, the encouragement fhould poffibly be confined to thofe counties which are upon the fouthern coaft. I have made fome obfervations upon other articles in Mr. Doffie's Memoirs, which, however, I will not trouble the Society with till I hear that the present may be thought interesting.
Believe me, dear Sir,
Your most faithful humble fervant,
To Samuel More, Esq.
ODE for the NEW-YEAR, As performed before their Majefties.
Written by William Whitehead, Efg. Poet-Lauren.
firmer ties than duty knows.
Torn rudely from its parent tree,
Will foon its genuine glory fee,
And feel their force, and lift an alien head;
And acts of mutual amity endear
Their manners and their arts the fame;
Enlarge the breach that longs to close;
Firm faith and cordial love, and wake the willing
To the SPANISH RIVALS. By the AUTHOR of the FARCE. And spoken by Mr. BANNISTER, Jun. WELLfare each heart that here has of confeft
The tender feelings of the human breast! Ther, virtue reigning, gives foft pity birth, And confcious virtue n'er was foe to mirth: