230 Mayow 



of the philosophers long ago. As if, indeed, human 

 ignorance should be nature's laughingstock, for those 

 things that are seen every day in our hand and before 

 our eyes recede furthest away from the grasp and 

 perception of our minds, like the unhappy case of 

 Tantalus. And among these Motion deserves to be 

 reckoned, for we know so little how it takes place 

 that, notwithstanding the evidence of our eyes, its very 

 existence has been sometimes considered doubtful, and 

 one of the famous questions discussed in the Schools 

 was — Is Motion to be taken for granted ? And the 

 Sophist so firmly denied this that it would have been 

 all up with its existence, had not Motion itself, stirred 

 up in its own defence, made answer, and set the Peri- 

 patetic against the Philosopher. But now, if there 

 are such various difficulties as to motion in general, 

 how much more obscure is that animal motion, in 

 which we see to our astonishment enormous bodies 

 execute quite stupendous movements of their own 

 accord. 



No one doubts that the movements of animals are 

 produced by the contraction of the muscles, but how 

 that contraction is brought about is the subject of 

 varied controversy among authors. Still, the most 

 generally received opinion is that the fibres of the 

 muscles are inflated with some elastic matter, so that 

 while they swell as to breadth they contract as to 

 length. 



And this inflation of the fibres is thus described by 

 that very distinguished man, Dr Willis, in his Discus- 

 sion on Muscular Motion. This learned man thinks, 

 namely, — "That the Animal Spirits carried from the 

 brain by the channel of the nerves are stored up in 

 the tendinous fibres, as in suitable repositaries ; but 

 that these spirits, on the incitement to motion being 



