WORK. 147 



kind, that he had no need for any elaboration, and I think 

 his habit in this respect was in great measure due to his 

 desire to husband his strength, and not waste it on inessential 

 things. 



His way of marking objects may here be mentioned. If 

 he had a number of things to distinguish, such as leaves, 

 flowers, &c., he tied threads of different colours round them. 

 In particular he used this method when he had only two 

 classes of objects to distinguish ; thus in the case of crossed 

 and self-fertilised flowers, one set would be marked with 

 black and one with white thread, tied round the stalk of 

 the flower. I remember well the look of two sets of cap- 

 sules, gathered and waiting to be weighed, counted, &c., 

 with pieces of black and of white thread to distinguish the 

 trays in which they lay. When he had to compare two 

 sets of seedlings, sowed in the same pot, he separated them 

 by a partition of zinc-plate ; and the zinc-label, which gave 

 the necessary details about the experiment, was always 

 placed on a certain side, so that it became instinctive with 

 him to know without reading the label which were the 

 " crossed " and which the " self-fertilised." 



His love of each particular experiment, and his eager zeal 

 not to lose the fruit of it, came out markedly in these cross- 

 ing experiments in the elaborate care he took not to make 

 any confusion in putting capsules into wrong trays, &c., &c. 

 I can recall his appearance as he counted seeds under the 

 simple microscope with an alertness not usually characterising 

 such mechanical work as counting. I think he personified 

 each seed as a small demon trying to elude him by getting 

 into the wrong heap, or jumping away altogether ; and this 

 gave to the work the excitement of a game. He had great 

 faith in instruments, and I do not think it naturally occurred 

 to him to doubt the accuracy of a scale or measuring 

 glass, &c. He was astonished when we found that one of his 

 micrometers differed from the other. He did not require any 



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