. III. GIZZARD OF THE FOWL. 65 



structure of the membrane some time after death ; but the 

 influence of the position of the two surfaces continues, to a 

 certain point, even in the altered membrane. We have, 

 indeed, remarked that the fall of the albuminous solution is 

 double, and even treble, in the endosmometer where the 

 external surface of the membrane is towards the inner side 

 of the instrument. 



Gizzard of the Fowl. With the mucous membrane of 

 the gizzard of the fowl, using a solution of sugar and pure 

 water, endosmose is stronger from the external to the inter- 

 nal surface of the membrane, though, in general, the differ- 

 ence of the elevation between the liquids of the two endos- 

 mometers is not very great. Thus, when the internal part 

 of the membrane was towards the interior of the instrument, 

 the elevation was 48 millimetres, whilst it was 43 in the 

 contrary position. It is not unusual to see in the first posi- 

 tion a certain elevation, as of 17 millimetres, of 20 milli- 

 metres, &c., whilst in the second the liquid remains un- 

 moved. We ought also to mention the promptitude with 

 which the current of endosmose from water to a solution of 

 sugar ceases, through the gizzard of the fowl. Generally 

 the liquid column becomes stationary in both tubes at the 

 end of two hours at most. 



Endosmose between water and the albuminous solution 

 through this membrane (the gizzard of the fowl) seems to 

 take place indifferently, whatever be the position of the sur- 

 faces with reference to the two liquids. We have proved 

 this fact several times. In a solitary instance we saw the 

 liquid rise 15 millimetres in the endosmometer, where the 

 internal surface of the membrane was towards the interior 

 of the instrument, whilst the liquid in the other instrument 

 only rose 5 millimetres. We obtained the same results 

 with a solution of gum as with the albuminous solution. 

 In both positions of the mucous membrane of the gizzard of 

 5 



