188 Dr. Wallace on 
various other observers, have satisfactorily proved that this insect, 
Bombyx Cynthia, will thrive well in this climate, in fact equally 
well with the tree (Ailanthus glandulosa) on which it feeds, and 
which has been naturalized in Europe more than 110 years ; similar 
statements have been received with reference to this insect and tree. 
from the Middle and Southern parts of Europe. 
Ailanthiculture in England demands only a practical demonstra- 
tion to assure success, all induce many to engage in a novel and 
promising industry. I propose therefore to investigate this sub- 
ject as far as it has hitherto been practic: lly tested in England. 
But it may be objected that the price of labour in rine) country 
is, by comparison with other countries, too dear to enable us to 
compete successfully with them. I reply, that after the first plan- 
tation, the principal labour required is that of women and children 
in rearing the silkworm, gathering the cocoons, and spinning the 
silk; that much less labour is necessary in Ailanthiculture than in 
mulberry silk culture ; that there is but little margin for much dif- 
ference in cost between women’s labour in England and elsewhere ; 
that it is very desirable to find suitable labour for women and 
children in rural districts ; that silk mills are common in England, 
and their owners (in process of time) will buy the new material and 
thus save the cost of carriage ; that the Ailanthus tree will flourish 
on very sterile soils, and thus lands hitherto not in cultivation, as 
for instance Dartmoor and Bagshot Heath (where Ailanthiculture 
is now being carried on), the embankments of railways, Irish bogs, 
Scotch mosses and other wastes may be cultivated with profit; 
and, lastly, practical experience in moist climates, as in England 
and Holland, seems to indicate that the Ailanthus tree grows more 
luxuriantly than in the arid soils of France, and that the insect 
attains a larger size and spins a larger cocoon; nay, it has been 
stated, that the silk of English cocoons is more glossy and of su- 
perior quality to the French specimens. But 1 do not conceal 
from myself that great difficulties attend the development of new 
ideas, before they can be practically successful. ‘The potatoe, now 
a daily article of diet, had to struggle for a long time against pre- 
judice and inexperience, and it required three centuries of cultiva- 
tion before the tuber which Raleigh brought over from America 
became developed into the ‘* Regents,” “ Flukes” and “ Ash-leaved 
Kidneys” of our tables. It is remembered how in time of scarcity 
of corn, at the close of the last century, the lower orders refused to 
substitute the potatoe as an article of diet in language such as this, 
** Shall we give our children pig’s muck ?” 
But to aHoeeedl now with the subject of Ailanthiculture : 
In the year 1856 a few living cocoons of a new silkworm were 
