FUNDAMENTAL PRINCIPLES OF DISEASE. 



By Rush Shippen Huidekopee, M. C, Vet. 

 [Revised by Leonard Pearson, B. S., V. M. D.] 



ANIMAL TISSUES. 



The nonprofessional reader may regard the animal tissues, which 

 are subject to inflammation, as excessively simple structures, as simi- 

 lar, simple, and fixed in their organization as the joists and boards 

 which frame a house, the bricks and iron coils of pipe which build a 

 furnace, or the stones and mortar which make the support of a great 

 railroad bridge. Yet while the principles of structure are thus sim- 

 ple, for the general understanding by the student who begins their 

 study the complete appreciation of the shades of variation, which 

 differentiate one tissue from another, which define a sound tendon or 

 a ligament from a fibrous band — the result of disease filling in an old 

 lesion and tying one organ with another — is as complicated as the 

 nicest jointing of Chinese woodwork, the building of a furnace for 

 the most difficult chemical analysis, or the construction of a bridge 

 which will stand for ages and resist any force or weight. 



All tissues are composed of certain fimdamental and similar ele- 

 ments which are governed by the same rules of life, though at first 

 glance they may appear to be widely different. These are (a) amor- 

 phous substances, (i) fibers, and (<?) cells. 



(a) Amorphous substances may be in liquid form, as in the fluid 

 of the blood, which holds a vast amoimt of salts and nutritive matter 

 in solution ; or they may be in a semiliquid condition, as the plasma 

 which infiltrates the loose meshes of connective tissue and lubricates 

 the surf ace of some membranes; or they may be in the form 'of a glue 

 or cement, fastening one structure to another, as a tendon or muscle 

 end to a bone ; or, again, they hold similar elements firmly together, 

 as in bone, where they form a stiff matrix which becomes impreg- 

 nated with lime salts. Amorphous substances, again, form the pro- 

 toplasm or nutritive element of cells or the elements of life. 



(&) Fibers are formed of elements of organic matter which have 

 only a passive function. They can be assimilated to little strings, or 

 cords, tangled one with another like a mass of waste yarn, woven 

 regularly like a cloth, or bound together like a rope. They are of two 



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