TELEOLOGY OF PALEY, ETC 17 



looking upwards or downwards ; and at the same time 

 of turning itself round upon the body to a certain 

 extent, the quadrant, we will say, or rather perhaps a 

 hundred and twenty degrees of a circle. For these two 

 purposes two distinct contrivances are employed. First 

 the head rests immediately upon the uppermost part of 

 the vertebra, and is united to it by a hinge-joint ; upon 

 this joint the head plays freely backward and forward 

 as far either way as is necessary or as the ligaments 

 allow, which was the first thing required. 



" But then the rotatory motion is thus unprovided for ; 

 therefore, secondly, to make the head capable of this a 

 further mechanism is introduced, not between the head 

 and the uppermost bone of the neck, where the hinge is, 

 but between that bone and the next underneath it. It 

 is a mechanism resembling a tenon and mortise. This 

 second or uppermost bone but one has what the ana- 

 tomists call a process, viz. a projection somewhat similar 

 in size and shape to a tooth, which tooth, entering a 

 corresponding hollow socket in the bone above it, forms 

 a pivot or axle, upon which that upper bone, together 

 with the head which it supports, turns freely in a circle, 

 and as far in the circle as the attached muscles permit 

 the head to turn. Thus are both motions perfect with- 

 out interfering with each other. When we nod the 

 head we use the hinge-joint, which lies between the 

 head and the first bone of the neck. "When we turn 

 the head round, we use the tenon and mortise, which runs 

 between the first bone of the neck and the second. 

 We see the same contrivance and the same principle 

 employed in the frame or mounting of a telescope. It 



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