412 Transactions. — Miscellaneous. 



carbonic acid is being decomposed and carbon absorbed ; evaporation is 

 taking place which requires that the root-fibres should take up water, and 

 that by some mysterious means, contrary to gravity and certainly not 

 owing to capillary attraction, the juices of the plant are sent to a distance 

 of sometimes hundreds of feet. All these changes imply motion. So also 

 does the growth of tbe plant. This is slow indeed in many cases, and par- 

 ticularly in cold or temperate climates, but so rapid in tropical regions 

 where there is abundant moisture in the soil, that plants may almost be 

 seen to grow. 



This motion is sufficiently powerful to overcome in the majority of cases 

 the force of gravity, and might be measured in foot-pounds. It will also 

 overcome the force of cohesion, as is seen where root-fibres penetrate dense 

 clay or split up solid rock. 



Motion caused by life alone is seen in the circulation of the blood, and 

 especially in that part of it which takes place in the capillary vessels. If, 

 as I have often done, you snip off the transparent part of the tail of a small 

 fish or a tadpole and place it under the microscope, you may see the blood 

 corpuscles rolling rapidly along for at least half-an-hour ; in some cases I 

 have watched them for an hour and a half, still in motion, although during 

 the latter part of the time the motion is much retarded : it seems to 

 continue until some physical change has taken place in the capillaries, the 

 result of their death. If at a suitable temperature suitable pabulum be 

 supplied, the motion of the blood in the capillaries may go on for hours 

 after somatic death has taken place. In some experiments I made a few 

 years ago in New South Wales I found that when portions of tadpoles' tails 

 placed under the microscope were supplied with a mixture of egg- albumen 

 and water, and kept at a temperature of 80° to 90° F., the circulation 

 continued as long as nineteen hours. The note made at the time is as 

 follows : — 



"11th (month not mentioned, probably February), 3 p.m. Put four 

 pieces of tadpoles' tails in albumen and water ; they floated ; corked the 

 bottle loosely with lint ; water was filtered but not boiled. Day hot ; 

 temperature 88° F. 



" Put three other pieces at the same time into some of the same water, 

 in the same kind of bottles stopped in the same way." 



" 12th, 10 a.m." (nineteen hours afterwards). " Night had been very 

 hot. Tails placed in water shrivelled slightly (shrunken) and extremity of 

 tail curled up. Under microscope numbers of detached round red cor- 

 puscles and quantities of Bacteria ; no leucocytes nor cell-growth of any 

 kind." 



