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which they give to the true Degree of Firmnefs and 
Elafticity in the fibres; the faline, fulphureous, and 
earthy Parts are all endued with a ftrongly attracting 
Power j and when brought into Contact with each 
other, or with the watry and aereal Particles, they 
oive Firmnefs and Solidity to the Compofition. 
XVI. 
Water feems to be the Gluten by which the other 
Principles are wrought up. Too much Water in the 
Gompofition renders the Fibres foft and lax 5 as in 
Children, and anafarcous People, Too little Moift- 
ore occafions a ftiff, rigid Fibres as in old Age. 
There is a certain Degree of Texture and Cohefion 
neceflfary towards mufcular Motion in its greateft 
Strength. 
XV IL 
F have (hewn in a former Treatife *, that Air is 
very inftrumental in fixing and uniting the other 
Principles which conftitute an animal Fibres for in 
the moft folid Parts of the Body* where the Cohe- 
fion is ftrongeft, we find great Plenty of Air. That 
the Air-Particles are capable of being united, and 
fix'd to folid Bodies, and by that means may be 
efteemed a Part of their Compofition, we have many 
evident Proofs in Dr. Hales’s Analyjis of the Air s 
and that thofe Particles do in their fixed State 
flrongly 
• Modern Theory of Phyfic, f. 56. 
7 
