CHYME TISSUES. 7 



replaced by any substance for the alimentation in the first 

 stages of infancy; the aqueous and vitreous humours of the 

 eye, the synovia which bathes and lubricates articulated sur- 

 faces, the tears, and the saliva, which we shall see later takes a 

 part in digestion, and in which Mons. Longet has shown the 

 existence of minute and therefore harmless proportions of 

 sulpha-cyanide of potassium, one of the most virulent poisons. 

 In popular language the term humour is applied exclusively 

 to the purulent fluids, morbid products which differ in some 

 particulars according to the conditions under and the organs 

 in which they are formed. It is unfortunate that they 

 should monopolize a term which belongs to all the organic 

 fluids. 



We shall merely point out the intermediate products, among 

 which figures the chyme, a semi fluid substance formed in the 

 stomach during digestion, and the excretions which the system 

 rejects, after having separated from them nearly all assimil- 

 able principles. 



The tissues are the solid parts of the body, formed of 

 anatomical elements either bound together or simply in 

 juxtaposition. The tissues are classed according to the 

 elements peculiar to them, according to their texture, that 

 is to say the mode in which these elements are arranged; 

 and according to their essential properties, which are either 

 physico-chemical, such as consistence, extensibility, retrac- 

 tility, elasticity, and hygrometricity, or organic, like the 

 properties of absorption, of secretion, of development, of 

 regeneration, of contractility, and of innervation. These 

 properties are variable according to the tissues, which are 

 more or less tenacious, more or less extensible, and so forth. 

 Or they are peculiar to certain tissues, and independent, for 

 a tissue may be retractile and not extensible or elastic, and 

 vice versa. Constituent tissues are those which, composed 

 of the fundamental elements, fibre, cell, and tube, form the 

 essential organism. Produced tissues are those which eman- 

 ate from the first, and may be detached from them without 

 destroying them, and are only accessory or complementary 

 parts. These products are normal or morbid, according to 

 their nature and substance. 



