VALUE OF THE MICROSCOPE. 45 



that they refuse to grow except in certain places, 

 and under pecuUar conditions ; for if their vege- 

 tation were general, the produce of the earth 

 would be almost entirely consumed by them. 

 There is no subject on which grosser mistakes 

 are made, even by writers well-informed on 

 other topics, connected with these fungi. The 

 cause is, that attention has not been properly 

 paid to it, from its apparently recondite na- 

 ture. But it is hopeless to expect a systematic 

 adoption of remedies while the veil of ignorance 

 invests the cause of disease. It was curious 

 to see, in the speculations on the potato disease 

 of 1845, how vague the ideas of their authors 

 were respecting the fungi. But the great im- 

 provements in modern microscopes will be 

 attended, it is hoped, with the increase of 

 much important knowledge. Under the able 

 management of Mr. Berkeley and others, these 

 instruments have already done wonders ; and 

 what a number of otherwise listless winter 

 hours might an agriculturist pass, with the aid 

 of a good Argand lamp, in acquainting himself 

 with these little pests which constantly attend 

 his labours. Farmers' clubs have multiplied 

 throughout our rural districts, and every one 

 ought to possess a microscope. There would 



