( 30 ) 

 AvS the quantity : represents in general the heat, whicii is gixen 



{l-\-r.vY 



oul [}iv nioleciile when an infinitely small quantity of the pure 



molten metal is mixed with the fluid metal mixture, the quantity 



«i.r;^ will represent that same quantity of heat for .i* = 0. 



We must here notice that the accurate values of and (/„ must 



be used, as well in equation (4) as in (5). So in the case of tin- 



mercuF}^ for instance 0=0,396 is accurate only if the mercury is 



solved into the tin as atom. If this is not the case — and in the 



example mentioned we liave every reason to suppose that the mercury 



is associated to an amount of 1,5 — then 6 must undergo a proj)or- 



AT 

 tional increase. was namely calculated from = -^-. It we api)ly 



T,v 



tiie condition in tiie form (5), then we must suhstitulo the cr^ierl- 



mentaUy determined vahie of the latent heat for r/o- 



So in the case of tin-uiercury will not be equal to 0,4 but in 

 reality to 0,6, and therefore 0' — ^iO-^H = 0,36 — 0,30 + 0,04=0,10, 

 from wliich the existence of a point of inflectioii appears still clearer 

 than in the supposition = 0,4. 



If we apply condition (5), a^ being equal to 0,0453x1690=77 

 Gr. Cal., we have certainly 



1700 <- --^1^ . 



•\ 77 



1 



505 



If (i^ is positire, as is the general case, then the siin[>le couditiou 



7,. < 4 T„ 

 will include condition (5). This latter form therefore will provide us 

 in nearly all cases with a reliable criterion whether or not a point 

 of inflection occurs in the melting-pohit curve. 



Physiology. — "On the epltheUnni of the .surface of the stotnach." 

 By Dr. M. 0. Dekhuyzen and Mr. P. Vermaat. Veterinary 

 surgeon. (Communicated by Prof. C. A. Pekelharing). 



We are accustomed to regard the stomach in the very first place as an 

 organ for the clijestion of food, for the preparation of the gastric juice. 

 About its power of resorption its not so much is known, (llucose, 

 peptones, strychnin, alcohol, dissolved in or diluted with Avater, are 

 resorbed by the gastric mucous membrane. The rapidity of resorption is 

 different in various kinds of animals. The structure of the cells wliich 



