464 PHILOSOPHICAL TRANSACTIONS. [aNNO I7OQ. 



motion as this could not be brought about, unless the vessel adep had a valve 

 at AD, where it is joined to the heart, which valve is to prevent the blood, that 

 is thrown into the heart, from returning the same way. And so likewise there 

 must necessarily be another valve at cd, to prevent the blood, that is protruded 

 from the heart, from flowing back again. 



Also fig. 24 represents the heart of a salmon, where klm shows that instru- 

 ment or vessel that was represented in fig. 23, by adef, as ino shows the same 

 as CDG in the said figure. 



Also the instrument klm being cut open, to discover with the naked eye, 

 the sinewy parts and their branches; these appeared as in fig. 25, in which gr 

 is the part that was joined to the heart, and is the same that in fig. 24 is repre- 

 sented by kl ; in the said fig. 25, we may observe how the sinewy parts and 

 their branches run from qlb. to t. This instrument, or vessel, is very soft in 

 its parts, and it seemingly is not strong. 



Fig. 26 is that vessel dissected, which in fig. 24 is represented by ion ; 

 which vessel is exceedingly thick and strong, and like that represented in fig. 25, 

 provided with strong sinewy parts, that when the parts are extended by the 

 blood poured into them, they may be able both in roundness and length to 

 convey the blood into the arteries: these parts, by reason of their great num- 

 bers, cannot be delineated in such manner as they ought to be. 



From the whole I conclude, that the heart protrudes the blood gently into 

 the arteries; and that the blood, which flows from the veins into the heart, 

 causes that sudden revulsion, called the pulse ; both because it cannot so im- 

 mediately pass through the valves, and because the veins in that part are a little 

 narrower, by which means there is a kind of stop or intermission in the circu- 

 lation of the blood : and this I conceive is the cause of that motion which we 

 call the pulse.* 



Several Experiments on the seeming Spontaneous Ascent of fVater. By Mr. 

 Fr. Ilauksbee, F.R.S. N° Sip, p. 258. 



ExPER. I. To satisfy myself, whether the form of the vessel might not 

 contribute to the spontaneous ascent of water in tubes, &c. I procured a couple 

 of glass planes, about 7 inches long, and 14- broad ; these planes were part of 

 a broken looking glass ; and though when clapped together, they seemed to 

 touch one another in so many parts, yet when they came to be immersed in a 

 liquid, it would ascend between them ; but it was so thin and colourless, that it 

 could not easily be discerned ; but on separating them, they would be found 



* It is scarcely necessary to remark, that Mr. L.'s conjectures respecting the cause aad oature of 

 the pulse are extremely erroneous and absurd. 



