Some by their industry and learning found
That all the blood like to the sea runs round:
From two great arteries it doth begin,
Runs through all veins, and so comes back again.
The muscles like the tides do ebb and flow
According as the several spirits go.
The sinews, as small pipes, come from the head,
And all about the body they are spread,
Through which the animal spirits are conveyed
To every member, as the pipes are laid.
And from those sinews-pipes each sense doth take
Of those pure spirits, as they us do make.