556 THE GARDENER. [Dec. 



South Kensington, in the arcades of the Royal Horticultural Society. 

 Numerous prizes in money are to be awarded, and competitors are 

 said to be coming from all the great towns in the kingdom with 

 their various inventions, for which numerous patents have already 

 been taken out. Putting aside the saving of fuel effected by such 

 means in towns — which would amount to millions in London alone — 

 the advantages to the health of the inhabitants, and to vegetation in 

 and near great centres of industry, would be almost incalculable. In 

 some manufacturing towns there are already laws in force for the con- 

 sumption of smoke from furnaces and the like, but they are prac- 

 tically a dead letter. The smoke hangs like a pall over towns and the 

 surrounding district for miles, and settles in the form of black smut 

 on field and forest, and may frequently be seen resting on the surface 

 of reservoirs and lakes in a thick black scum of the consistency of 

 cream. A smoke-consuming appliance is also much wanted in stoke- 

 hole furnaces in gardens. The smoke produced by these is a serious 

 nuisance in all large gardens : hothouses and conservatories get quite 

 blackened in a short time by the soot, which greatly spoils the appear- 

 ance of these structures. There is a way of consuming the smoke to 

 some extent, if the stoking is intelligently performed ; but this cannot 

 be depended upon in gardens, and none of our horticultural boilers 

 present facilities for effecting that end themselves. The use of coke 

 instead of coal will go far to lessen the evil. Indeed a coke-fire is 

 absolutely smokeless soon after it is lit ; but gardeners complain that 

 they cannot keep up temperatures with it sufficiently, unless the quan- 

 tity of piping is greater than is usually provided. Coke, too, is more 

 expensive. Any of our hot-water engineers who will provide a readily 

 available smoke -consuming apparatus for garden furnaces will make 

 his fortune. 



After all, those who have entertained and acted upon the idea that 

 the potato-disease might be eventually overcome by the selection of 

 disease-resisting varieties, and propagating from these, are justified 

 by the discoveries of M. Pasteur, which have attracted so much atten- 

 tion of late. The silk-worm disease, this investigator discovered, was 

 caused by tiny microscopic corpuscles or organisms in the juices of the 

 diseased worms, which even extended to the eggs produced by them. 

 By careful breeding from eggs, however, which happened to be free 

 from the disease-germs, although produced by disease-affected worms, 

 he showed that in a short time it would be possible to regenerate the 

 race and entirely stamp out the disease ; and that when circumstances 

 did not admit of elaborate precautions, a seed might be secured, which, 

 if not absolutely free from disease, would still afford a very satisfac- 

 tory crop of silk. The silk-worm and the potato are two very different 

 subjects, no doubt, but there is no physiological reason whatever for 

 supposing that the potato-disease cannot be overcome in the same way; 



