8 REPORT OF THRE COMMISSIONER. 
STEAM-PLOWING. 
The inventive mind of the country is strongly stimulated with the 
hope of educing a distinctively American machine, better adapted to 
the peculiar necessities of our agriculture than the most successful for- 
eign apparatus. The Report for 1869 contains descriptions and illustra- 
tions of several patents of that year, and the volume for 1870 will show 
that these efforts have been continued during the present year. It isto 
' be regretted that so many still adhere to the impracticable idea of loco- 
motive traction. The reports of the actual work of the five steam-plews 
now in operation in this country are extremely favorable to the idea of 
ultimate success in the solution of the problem of steam-plowing as an 
adjunct of our agriculture. 
SILK CULTURE. 
Silk culture in California has been attended with great success up to 
the present time, producers claiming that the climate of that State is 
peculiarly adapted to the rearing of silk-worms, on account of the dry- 
ness and equality of the temperature, and the rare occurrence of severe 
thunder storms. In Utah experiments have been made, with success, in 
feeding the worms upon the leaves of the Osage orange instead of the mul- 
berry. The Japanese silk-worm, Samea cynthia, on the ailanthus, is now 
perfectly acclimated, and breeds in the open air in Brooklyn, Philadel- 
phia, and other places, but as yet I have heard nothing of the use of its . 
cocoons in manufacture. Two other silk-producing worms, Aitacus yama 
mai and pernyi, have been bred this season in Brooklyn, but are yet too 
scarce for a proper test of their value. 
GOVERNMENT PLANTATIONS OF CINCHONA TREES. 
Among the trees which may be introduced and acclimatized in our 
territory, there is none deserving more consideration than the Peruvian- 
bark tree. Both England and France have deemed it necessary, in view 
of the increasing scarcity of quinine, to establish ih their colonies planta- 
tions of the Cinchona tree. Its essential product is furnished to the 
world from a narrow belt on the slope of the Andes in Peru and Bolivia. 
The supply is limited and precarious, with no means of extension by 
propagation or cultivation in these Soutk American nations. The tree 
is of rapid growth in favorable localitiés, and after six years may be- 
come an article of commerce. The commencement of cultivation ought 
not to be left to private enterprise, bu¢ should be initiated and supported 
in its early infancy by the establishment of one or more national planta- 
tions at points selected on accountof their favorable climatic influences. 
The time is now opportune for commencing such a work, since a supply 
of young trees is easily obtainable from a source whence no real diffi- 
culty arising from transport and transplantation would oceur. 
The propagation of the Cinchena has been commenced in the experi- 
