NATURAL THEOLOGY. Ill 



That is the thing to be remarked, and any one 

 may remark it in carving a neck of mutton. Tiie 

 manner of it is this: the end of the rib is divided 

 by a middle ridge into two surfaces, which sur- 

 faces are joined to the bodies of two contiguous 

 vertebra}, the ridge applying itself to the inter- 

 vening cartilage. Now this is the very contri- 

 vance which is employed in the famous iron 

 bridge at my door at Bishop-Wearmouth, and 

 for the same purpose of stability, viz., the cheeks 

 of the bars which pass between the arches 

 ride across the joints by which the pieces com- 

 posing each arch are united. Each cross-bar 

 rests upon two of these pieces at their place of 

 junction, and by that position resists, at least in 

 one direction, any tendency in either piece to slip 

 out of its place. Thus perfectly, by one means 

 or the other, is the danger of slipping laterally, or 

 of being drawn aside out of the line of the back, 

 provided against; and, to withstand the bones 

 being pulled asunder longitudinally, or in the di- 

 rection of that line, a strong membrane runs from 

 one end of the chain to the other, sufficient to re- 

 sist any force which is ever likely to act in the 

 direction of the back or parallel to it, and conse- 

 quently to secure the whole combination in their 

 places. The general result is, that not only the 

 motions of the human body necessary for the or- 

 dinary offices of life are performed with safety, 

 but that it is an accident hardly ever heard of that 



