362 THE LYMPHATIC SYSTEM. 



The nature of the membrane employed, and even its position in re- 

 gard to the two liquids, also influence the result. Different serous and 

 mucous membranes act with different degrees of force. The effect pro- 

 duced is not the same with the integument of different animals, nor with 

 membranous tissues taken from different parts of the body of the same 

 animal. This depends upon the fact that the power of absorption for 

 a given liquid is different in different tissues. Chevreuil investigated 

 this point by taking definite quantities of certain animal substances, and 

 immersing them in various liquids for twenty-four hours, at the end of 

 which time the substance was removed and weighed. Its increase in 

 weight showed the quantity of liquid which it had absorbed. The fol- 

 lowing table 1 shows the result of these experiments : 



COMPARATIVE POWER OF ABSORPTION IN DIFFERENT TISSUES. 



100 Parts of Water. Saline Solution. Oil. 



Cartilage, 1 f 231 parts. 125 parts. 



Tendon, 178 " 114 8.6 parts. 



Elastic ligament, I absorb in I 148 " 30 " 7.2 " 



Cornea, f 24 hours, j 461 " 370 " 9.1 " 



Cartilaginous ligament, 319 " 3.2 " 



Dried fibrine, [301 " 151 " 



The influence of the position of the membrane depends upon a similar 

 difference in the absorbing power of its two surfaces. With some 

 fluids, endosmosis is more rapid when the membrane has its mucous 

 surface in contact with the dense solution, and its dissected surface in 

 contact with the water. With other substances, the more favorable 

 position is the reverse. Matteucci found that, in using the mucous 

 membrane of the ox-bladder, with water and a solution of sugar, if the 

 mucous surface of the membrane were in contact with the saccharine 

 solution, the liquid rose in the endosmometer between 80 and 113 milli- 

 metres in two hours. But if the same surface were turned toward 

 the water, the rise of the column of fluid was only 63 or 12 millimetres 

 in the same time. 



Another important circumstance is the constitution of the two liquids 

 and their relation to each other. As a general thing, if the liquids 

 employed be water and a saline solution, endosmosis is more active, the 

 more concentrated is the solution in the endosmometer ; that is, a larger 

 quantity of water will pass inward toward a dense solution than toward 

 one which is dilute. But the force of endosmosis varies with different 

 liquids, though they may be of the same density. Dutrochet measured 

 the force with which water passes through the mucous membrane of the 

 ox-bladder, into different solutions of the same density, with the follow- 

 ing result : 3 



1 In Longet, Trait6 de Physiologie. Paris, 1861, tome i. p. 383. 



2 In Matteucci, On the Physical Phenomena of Living Beings. Pereira's 

 translation. Philadelphia, 1848, p. 48. 



