On Vortex Motions. 



127 



projection, that is to bifurcate ; and this we find is the general 

 form of arteries and veins in the animal system. The prin- 

 ciple of this form of motion I have endeavoured to follow- 

 carefully by experiment, the result of which I shall be able 

 to show you. 



Taking a narrow glass trough filled with water and project- 

 ing from the upper surface a small current of Indian ink, we shall 

 see that the ramifications which the stream of ink undergoes,, 

 under the resistance of the water through which it passes, out- 

 wardly resembles the separation of veins and arteries in the 

 animal system. 



This action I am able to show for the first time by means of 

 the magic lantern * 



Fig I. — The Ink Stream, Fig 2. — The Terminal Projections 



natural size. enlarged. 



The termination of the bifurcated projections of the ink 

 stream are worthy of special attention. These terminations 

 begin to bifurcate within themselves and at first form terminal 

 knobs. This knob termination I conceive to be analogous to 

 the termination of many vascular vessels in the animal body ; 

 as, for example, those termed pacinian bodies, which form the 

 nerve-endings of the lymphatics ; the termination of sweat 

 glands ; and the malphigean bodies in the kidneys. These 

 I propose only as similarities, but if the mechanical principles 

 proposed are in degree active, they must in all cases be con- 

 sidered under much differentiation by othfer active principles 

 existing (known and unknown) in the animal system. 



If we assume such mechanical principles to be active in vital 

 systems as those proposed (differentiated doubtless in these by 



* The illustrations are taken from Mr. Stanley's work on " Fluids." 



