148 STEPS IN TRUE SCIENCE 



fungus appeared ; and where it was not actually 

 seen externally on the leaves, it seems to 

 have exercised an influence on the tubers, 

 which are, in fact, branches or stems under 

 ground, as every botanist knows. Several 

 other curious fungi have also been seen in the 

 tubers, which have not yet been fully de- 

 scribed. 



Enough has been said to show the extreme 

 importance of more complete knowledge of the 

 habits qf parasitic moulds, and of the circum- 

 stances favourable or unfavourable to their 

 development. It is hoped that what is now 

 about to be detailed on that subject, as the 

 result of experiments, will be regarded as a step 

 in the right direction. Such steps must form 

 the commencement of all useful discovery. 

 Sound knowledge seldom takes a great leap 

 when it first comes amongst us : it enters by 

 slow and sure movements. The light of 

 genuine science first appears as a spark, which 

 subsequently is fanned by industry into a 

 flame ; false speculations, on the contrary, are 

 mostly a blaze of straw. 



It is purposed, in pursuing these inquiries, 

 first, to advert to the experiments made by 

 Dutrochet, one of the most ingenious of French 



