16 



Thus it passes alternately through and between the 

 plates, till it is diffused throughout. In this manner it 

 is diffused through bones, whose plates are contigu- 

 ous. But where the plates are at a distance, the 

 small cells contain glands, which directly supply the 

 plates with marrow* 



The marrow not only serves to keep the substance 

 of the bane moist, but to lubricate the joints, and to 

 hinder the ends of the bane from being worn or 

 ver-heated with motion. It also moistens the Liga- 

 ments, which tie them to each other : as do likewise 

 the glands found in all the joints. The backbone hath 

 these two things peculiarly remarkable. 1. Its dif- 

 ferent articulations from the other joints of the body. 

 For here most of the joints are flat,and withal guarded 

 with asperities and hollows, made for catching and 

 holding ; so as firmly to lock and keep the joints 

 from luxations, but withal to afford them such a mo- 

 tion, as is necessary for the incurvations of the body. 

 2. The difference of its own joints in the neck, back 

 and Idas. In the neck the two upper vetebrae are 

 curiously made, and jointed (different from the rest) 

 for the commodious and easy bending and turning 

 the head every way. In the thorax, and back, the 

 joints &re more close and firm ; and in the loins more 

 lax and pliant; also the knobs and sockets are turned 

 a quite contrary way, to answer the occasions the body 

 hath to bend more there, than higher in the back. So 

 that, us structure is the very best that can be contrived;, 

 for had it been all bone, we could have had no mo- 

 tion in our body ; had it been two or three bones 

 articulated for motion, the medulla spinalis must 

 have been necessarily bruised at every angle or joint;, 

 besides, the whole would not have been so pliable, 

 for the several postures we have occasion to put our- 

 selves in. If it had been made of several bones with- 

 out intervening cartilages, we should have had no 

 more use of it than it' it had been but one bone. If 

 each vertebra had had its own distinct cartilage, it 

 might have been easily dislocated. And lastly > the 



