weaken the merit of the applioant and "[ l"« •■'.^'^'8 

 i„ vom- interest! On the contrary, M. d'Arcet 

 has Slated himseU tliat it was M. Beauva.s who, 

 rnrtakin" of the opinion which tliat savant had 

 f,'„-,ne.l intravelliMg, of the mode or process pur- 

 surd in the So.nh, had induced him to ,h;fine his 

 own ideas on the suhject, and to form a phm ot a 

 ^alnhrious habitation. French agriculture will 

 be pleased, therefore, I hope, to unite in the same 

 sentiment of esteem, the savaM and the practical 

 man 1 say French agriculture, liecausc it does 

 not admit of a donht, if the important experiment 

 which is submitted to you is to have so high an 

 influence on the production of silk, in the central 1 

 and northern parts of France, that it will much 

 more efficaciously still contribute to the ameliora- 

 tion of the method of process pursued in the 

 South Let, therefore, those who are most cau- 

 tious let those ancient cultivators, who have so 

 much right to entrench themselves under that 

 rrudence which we respect in them, and which is 

 the treasure of their whole lives, at least, there- 

 fore wish that similar attempts may be renewed 

 and propagated. But the subject -is so important, 

 the question is so grave, that I ask of you, gentle- 

 men permission to enter again into some details, 

 preceded by a short recapitulation of the condi- 

 tions essential to a successful process of manage- 

 ntent, and of the means put in practice to the 

 ^ present day, to purify and refider healthy the hab- 

 itations of silk worms. If we study with care 

 the organization of these worms, which breathe 

 only through their stigmas, and if we analyse the 

 eases which they expire, particularly in the last 

 ages, we shall soon be convinced of the importance 

 of a mild and continual circulation of air, in a 

 room whore millions of these little insects must 

 be amassed together, and spread upon the hurdles 

 from wlience the unhealthy exhalations are 



evolved. . , , , 



In observing, attentively, the continual labors 

 which these small bodies are performing, as well 

 as the effects of dilation and contraction, which 

 are constantly taking place with these insects 

 particularly at the period of their moulting, it w.l 

 be perceived that all their functions are performed 

 with more or less quickness and facility, accord- 

 iu" to the degree of heat to which they are ex- 

 po'se.l ; and every one must be sensible of the 

 danger to which sudden changes of temperature 

 must expose them. 



Great humidity, of which the least inconve- 

 nience is to produce fermentation of the litter, is 

 fatal to the worms which are breathing the un- 

 healthy gases ; consequently cultivators dread, 

 particularly in the fifth age, the warm and damp 

 winds from the South. Within the habitations, 

 besides the external humidity, there is still devel- 

 oped a great quantity, which proceeds fronz the 

 leaves, and from the worms themselves. 



Dryness of the air, besides that it is essentially 

 injurious to the worms as to all animals, even when 

 it is the purest possible, suddenly dries and withers 

 the leaves ; and the worms which feel instinctively 

 the want of a certain quantity of water in their 

 aliment, refuse the leaf as soon as it is willed ; 

 consequently the worms suffer, and the leaves are 



lost. 



All cultivators know from their own experi- 

 ence, how important it is to fulfil the conditions 

 of continually renewing the air, of constant equal- 

 ity of temperature, and of hygromotric invariable- 

 ness ; but from the want of means to comply with 



them, thev are obliged to guard against the conse 

 quenl inconveniences, and for this purpose they 

 are in the habit of burning in the room aromatic 

 plants, of boiling vinegar, into which cloves are 

 nut of sprinkling the worms with the chloride of 

 lime &c. But the insufficiency and even the 

 ilan.'er of such process may easily be conceived. 

 ' Dandolc, a skilful cultivator of Piedmont, was 

 not lono- in convincing himself that these mejms 

 were fawl to good management, and he very soon 

 completely reformed the method pursued. To 

 purify and render healthy the habitations of silk 

 worms, he caused holes to be pierced in the floor 

 the ceiling and the walls, for the purpose of 

 renewing the air ; he repelled fumigations, of 

 the danger of which he was aware ; and in the 

 establishments constructed after his plans, and 

 called dandolieres, his imitators, who, unfortunately 

 are few in number, because encouragement has 

 been wanting at Piedmonl, obtain 100 to 110 

 pounds of cocoons instead of 50 or 60 to the ounce 

 of seed Here, in France, the question being 

 brought before you, encouragement will not be 

 wanting. 



In" the mean time the system of Dandolo is 

 still defective ; he established his fire-places within 

 the habitation itself, the immediate action of the 

 heat developed,- and of the exhalations spread 

 from the combustibles, could not but be pernicious 

 to the worms. Besides his methods are often 

 ineffectual, particularly in Jieavy and ftormy 

 weather, when the circulation of the air is dilii- 

 cult and when they are obliged to have recourse 

 to fumigations of the chloride of lime, the appli- 

 cation o> which it is not possible always to malie 

 ith the desired regularity. 



It is, therefore, necessary to employ more pow- 

 erful means, and which will be infallible in the 

 application of the principle of purification tuid 

 health developed by Dandolo; it is then that 

 science truly takes possession of the question ; it 

 annihilates completely the action of external influ- 

 ences, transports without the habitation the source 

 of heat, and thereby realizes simultaneously, the 

 four conditions essential to the success of the 

 process pursued. , , , • ■ > 



In the system of M. d'Arcet the habitation of 

 the silk worms is in the first story, the fire-iilace, 

 or :cklorifere, is on the lower floor, in a tight room 

 called an air chamber. The air passing out of 

 this room, is conducted by tubes placed the whole 

 len-nh of the floor «f the habitation, and is let 

 into it by means of circular openings, of various 

 sizes. In the ceiling is arranged a syslem of tubes 

 and of openings, corresponding exactly with the 

 one below ; it is through these upper openings 

 that the air, powerfully attracted by a ventilator 

 aiid by draft stove (fourneau d'appc!) fixed in the 

 chimney itself, which receives the funnel of the 

 calorifere, passes out, aftf r having been introduced 

 hito the habitation, and this draft produces another 

 in the air of the lower room, so that it establishes 

 a continual current. It is only necessary, there- 

 fore, to establish a room, not large, conveniently 

 situated, as to temperature and humidity. This 

 result is' easily obtained, by producing in it, with 

 the aid of a calorifere, ice, wet cloths, and drying 

 matters, heat, cold, humidity and dryness. 



in the month of April* 1835, M. C. d'Arcet sent 

 his plan of a salubrious habitation to M. Beauvais. 

 The time for commencing the operations for the 

 season was approaching; to let this period pass, 

 would be to delay, for an entire year, the applica- 



tion of the system and the knowledge of its results. 

 M Beauvais was impatient to put in practise the 

 work of science which his own experience en- 

 sured him the success of; in a month, he arranged 

 a new habitation, from which, by judicious man- 

 a<'enient, he has been enabled to derive every 

 advantao-e; he remedied as much as possible the 

 imperfections which must necessarily have result- 

 ed from the haste with which the arrangements 

 were executed, and from the novelty itself of the 

 system applied to the management of silk worms. 

 M Beauvais immediately found in the impor- 

 tant result which he ob-vn-d, t!ic rewa.;.; of his 

 cares and his assiduity,* and he flatters himself to 

 liave demonstrated mere explicitly, than it has 

 been previously done under our climate, thanks to 

 the syst.Mii of purification of M. d'Arcet, for the 

 application of which one attentive and careful 

 operative is only necessary, that a new era may 

 commence in the management of silk worms. 



However, gentlemen, if the important fact 

 ' which has just been accomplished near the capi- 

 tal, seems to support the hopes which many 

 enlightened men have entertained, it must be said, 

 it must be repeated, for the cause of truth itself, 

 which would repel an equivocal triumph ; that 

 whatever confidence this remarkable exjieriment 

 merits, and has already obtained, it presents itself 

 yet, as only one isolated fact, entirely recent, at 

 present deprived of the weight which it can only 

 obtain by a repetition of it, performed by difl'erent 

 I persons under other circumstances, and in other 

 places, and which must thus receive the sanction 

 of time. 



The author of this experiment, without (.'oubt, 

 merits encouragement; the attention of those 

 which it interests must be at once awakened, and 

 perhajis continued ; new essays appear to be desi- 

 rable to the real friends of our prosperity ; and it 

 is of great importance that these essays should be 

 continued ; for that which has excited your atten- 

 tion, has excited that of the skilful cultivators of 

 the 'south ; strangers as they are to undue pre- 

 possession, and superior to prejudice. They will 

 wait these new attempts with eugerness, the more 

 reasonably, because they well know that whatever 

 experiments are now making in the North, can 

 only turn to the ipiofit of the South, ready to seize 

 with gratitude new methods which shall a|ipearto 

 them sufficiently tested ; they know that the 

 branch of industry by which great fortunes have 

 been founded in the South; will be able, without 

 injuring them, to create in the North similar for- 

 tunes, in gradually relieving our connnon country 

 from the tribute of 43 millions wl.iich it pays at 

 this time to foreigners, and which the cultivators 

 of the North; in future emulous, but not rivals, 

 of those of the South, will be able, in a quarter 

 of a century, to share with them as brethren, with 

 constantly increasing benefit^ 



From these various considerations, gentlemen, 

 your committee of agriculture have directed me 

 to propose to you to insert the present report in 



•The price current for gi-cge silk is at this moment 

 25 fr. the demi-kilogr. M. Bea.ivais sells Lis at 50 fr. 

 It is of that beautiful kind called Sina (used in the maa- 

 ufaclure of gauze), which Louis XVI. imported from 

 Canton in 1784, which has been gradually delerioraled 

 in quali'ly, from the ncgligen.e and avarice of its origi- 

 nal producers; which M. Poidehurd has, by long and i 

 assiduous exerlions, re;;eni?iated in a remarkable de- 

 gree, and which M. IJeauvais is endeavoring to repro- 

 duce in all its primitive beauty. 



