SCIENCE-GOSSIP. 



207 



without suffering. The question is not at all 

 absurd. 



Speaking broadly, there is a general sensibility in 

 all living bodies, a sensibility, however, essentially 

 different from that property of nervous matter to 

 which we owe our capacity of the five senses. 

 Every living being, or otherwise living substance, 

 is sensible, if by sensibility we understand that 

 modification produced in living beings by stimu- 

 lants, that is, by light, heat, electricity and 

 moisture. Living matter reacts under the influence 

 of stimulants, and it is this that constitutes the 

 sensibility common to plants and animals. This 

 first phase of sensibility is the same in all 

 living beings, from the humblest plant to man, 

 the highest animal. It is the modification of 

 living matter produced by stimulants. In the 

 economy of the plant all is arrested there ; but in 

 animals there is another phase — the action pro- 

 duced on the brain. A cord under tension, for 

 example, may be made to vibrate and the vibratory 

 movements of the air are transmitted to the diffe- 

 rent parts of the ear and reach the acoustic nerve- 

 So far there is only a movement of a certain nature 

 and the changes produced on the nerve under the 

 influence of that movement. An impression is 

 made ; how effected we do not know. 



We now enter the domain of philosophy, on the 

 threshold of which the physiologist, well advised, 

 halts. The eye is struck by the luminous rays, 

 and the optic nerve is modified : that is sensibility 

 from the physiologist's point of view. Then sensa- 

 tion is produced, and the eye sees : that is sensi- 

 bility in the proper acceptation of the term. It is 

 merely a question of understanding, and not 

 confounding, distinct phenomena under the one 

 term. Still, even in the first phase, is sensibility 

 identical in all living beings ? Claude Bernard 

 answers in the affirmative. There is only 

 one kind of sensibility, since plants and 

 animals under the influence of ether or chloro- 

 form exhibit similar effects. The animal or man 

 inhaling ether or chloroform is soon plunged into 

 somnolence, the limbs become flaccid, and placed in 

 any position whatever, they remain thus, impotent 

 to move. In that state we may experiment with 

 the animal, or perform operations on man ; neither 

 is conscious of pain. Further, the action varies 

 with the animal and the duration of the inhalation. 

 It requires five minutes to anaesthetise a dog, a cat 

 less, a hare still less, a rat least of all; and no 

 animal is more rapidly anaesthetised than a bird, 

 even the feeblest quantity of ether being sufficient. 



Certain plants under the influence of chloroform 

 exhibit effects analogous to those of animals. 

 Thus, the sensitive plant refuses to exhibit its 

 peculiar behaviour when anaesthetised. When 

 under the influence of ether or chloroform it appears 

 to lose its sensibility, its leaflets are pendant and 



quite inert, it is indifferent to the application of 

 other stimuli, the whole plant is, as French 

 physicians say, resolu. 



Take an aquatic plant and place it in a bottle 

 containing a small quantity of ether or chloro- 

 form. No change appears in the plant, and one 

 would think it quite normal. Collect the gases 

 and examine them, and we learn that the plant 

 is exhaling carbonic acid (COo) and appropriating 

 oxygen, while in its normal condition it fixes the 

 carbon and rejects the oxygen. Transfer the plant 

 to fresh water, and it will begin to live as before. 



A germinating seed may be anaesthetised. Place 

 a cress seed, the germination of which is most 

 rapid, on a wet sponge, and a few hours after the 

 rudimentary stem and root will appear. Cover the 

 sponge with a bell, and under it introduce the 

 vapours of ether. At once development is arrested. 

 The plant is not dead, it is simply in a state of 

 lethargy; for if the bell is removed, and a current 

 of fresh air passed over it, it will again begin to 

 germinate. 



May we not conclude from these facts that 

 sensibility is of the same nature in plants and 

 animals ? And because ether acts upon both, may 

 it not follow that the effects are identical ? To 

 answer that question, it will be necessary to study 

 the phenomena of the simple cell. It is to the cell, 

 that living unit, we must go to observe the action 

 of anaesthetics. Animal and vegetable cells lose 

 their transparency under the influence of ether, 

 and recover it soon after that excitant has been 

 removed. Life is suspended as long as the cell is 

 opaque, and reappears with the cell's transparency. 

 The seat of sensibility is in the cell ; and the 

 identity of the cell, as well as the identity of their 

 modes of action under ether, justify the inference 

 that the sensibility is of the same nature. That, 

 however, is merely the first phase of sensibility, 

 and we may not infer that the plant is amenable 

 to joy and sorrow. 



All living beings, therefore, have something in 

 common, a relationship more or less close accord- 

 ing to the beings considered in the two kingdoms. 

 The cause which determines the evolution of the 

 body in plants and animals, the phenomena to 

 which that evolution gives rise, are the same. 

 There is not a material life proper to plants, 

 and another proper to animals, the same life 

 animates all. 



May it not be the same with instinct ? Is instinct 

 not common to the plant and the animal, if not 

 wholly at least in part ? The movements of plants 

 natural or provoked, are the result of physical, 

 chemical and physiological actions. There is 

 nothing unreasonable in the view . that certain 

 movements of the animal may be explained in the 

 same way. 



(To be continued.) 



