$42 CHINESE MODE OF REARING SILKWORMS, 
the health and vigour of silkworm caterpillars ; and 
next to this is plenty of free room for them to move 
about, the space being extended as they increase in 
size. 
«© When the insects are about to commence their 
spinning, mats are provided, in the centre of which 
a strip of rush, about an inch broad, is fixed, and 
extended in a spiral form, or in concentric circles, 
over the whole surface of the mat, having an area 
of about an inch broad between each circle, Here 
the worms fix themselves to spin ; and it is found 
that these receptacles occasion less silk to be wasted 
by them in floss, than where more space is allotted 
wherein their first threads can be spun. At this 
time the whole room is carefully covered with mats, 
to exclude the outward air and the light, as it is 
believed that silkworms work more diligently in 
darkness.” * This last idea, we have no doubt, is 
a vulgar error, for we should conceive the contrary 
to be the truth ; and, indeed, closing up the rooms 
must haye the effect of preventing the free cireula- 
tion of air, and consequently of injuring the health 
of the.caterpillars. Indeed Count Dandolo found, 
by strict observation, that this practice had a most 
pernicious effect. The Count says, that on visiting 
apartments where silkworms were reared, that on 
the side where the sun shone directly on the hurdles 
* Cabinet Library, Silk Manufacture, p. 126. 
