2 Proceedings of the Royal Irish Academy. 



ablj" distinguishing, — I refer to certain of those movements which hare 

 been termed vital movements. 



" One characteristic of every kind of living matter," Dr. Beale 

 observes (Protoplasm, pp. 402), " is spontaneous movement." It 

 requires to be noted that there the term " spontaneous " implies a fore- 

 gone conclusion. In order that the question should be an open one, 

 it is necessary to amend this, and say — " One characteristic of every 

 kind of living matter is movement, the causes of which are unknown, 

 and which therefore has been called ' spontaneous movement.' " 



"This," he adds, "unlike the movement of any kind of non-living 

 matter yet discovered, occurs in all directions, and seems to depend 

 upon changes in the matter itself, rather than upon impulses communi- 

 cated to the particles from without." 



Now, from facts which have been under my observation during the 

 space of two years, I have been brought to believe that similar move- 

 ments take place in matter which would be called non-living, and that 

 they, occurring in all directions, are due to a transformation of heat 

 into a propulsive force. 



Dr. Beale describes the alterations in form to which he has thus 

 alluded as characteristic of vital matter : and as they to a considerable 

 extent simulate those alterations in non-vital matter, it is desirable to 

 give his words : — " The alteration in form," he remarks, speaking of some 

 minute amcebae — the most minute he could discover — " was very rapid, 

 and the different tints in the different parts of the moving mass, result- 

 ing from alterations in thickness, were most distinctly observed. The 

 living bodies might, in part, be described as consisting of minute 

 portions of very transparent material, exhibiting the most active move- 

 ments in various directions in every part," . . . " and," he adds, "ca- 

 pable of absorbing nutrient materials from the surrounding medium." 

 That we must eliminate, as not being simply the manifestation of so- 

 called vital motion. He proceeds: "A portion which was at one 

 moment at the lowest point of the mass would pass in an instant to the 

 highest part. In these movements one part seemed, as it were, to pass 

 through other parts, while the whole mass moved now in one, now in 

 another direction, and movements in different parts of the mass occurred 

 in directions different from that in which the whole was moving." 

 " "Wliat movements in lifeless matter," he asks, "can be compared 

 with them? The movements above described,'' he adds, " continue as 

 long as the external conditions remain favourable ; but if these alter, 

 and the amoebae be exposed to the influences of unfavourable circum- 

 stances — as altered pabulum, cold, &c. — the movements become very 

 slow, and then cease altogether." 



Now, my attention was called to movements, very like these, which 

 take place in non- vital matter by certain phenomena which I observed 

 to occur under the microscope, in the minute globules of pyrogenic oil, 

 which float about in the tobacco smoke. These globules, as I stated, 

 at the time seemed twirling about like so many monads — but more 

 than this, they seemed to alter their form. Conscious that rapid 



