( i-^ ) 



Tlio points whei-e llio transfbniialioii lines oommonec to rnn straijïlit, 

 so the points of equililn-ium, also contbrni in this ease to an equation 

 siniihiL' to that used for eanesngai'. (.Ilucose is here the only product 

 of ijiversion ; we niiuiit, therefore, expect tiiat the undisturbed trans- 

 formation velocity would he here: 



\ X [a—xY I 



— d ,c =z ni I ■ — — <j I ilt 



{.c -|- n{a-.v) X -f n{a-ir)) 



and the e([uilil>riuni e([uation, therefore: 



1 — // — qa 1/'^ = 0. 



For 10 grams of maltose in J 00 cc. we experimentally found 



// = 0.J5. 



0.85 

 This gives q = ^ or, practically, 4, therefore the same coefficient 



as for canesugar ^). 



If in the above equation we substitute ^ m: 4 ; or 



1 _ ,/ ._ 4 ,( f — 0, 



the calculated points of equilibrium become for 



This is therefore in accordance with the experiment. 



The well-known researches of Croft Hill '') on the re^'ersal of 

 maltose gave points of equiliVtrium which were situated at a more 

 advanced transformation; for instance in a lO'/o solution y = 0.94.5. 

 These equilibria were attained only after days and weeks; the 

 above cited after a few minutes. 



Afterwards ^) Hill himself demonstrated that the resulting biose 

 was not maltose but an isomer, which he called revertose. In Hill's 

 numerous experiments, all the glucose was no doubt in the ^^form. 

 The synthesis found by Hill was thei-efore a combination of two 

 molecules of |i-glucose to a ne\v biose, isomeric with maltose *). 



1) The dilïusion velocilies on whicli depends the velocity of lueeling of two 

 molecules, cannot diller niucli lor glucose and laevulose. 



2) Journ. Chem. Soc. 1898 p. 634. 



'^) Journ. Chem. Soc. 1903 p. 578. Emmeulinu (Ber. 8i, p. GOO) had found 

 isomallose as reversal product. 



*) Most of the natural gliicoside.s appear to be compounds of hi- or semi-rotatory 

 liexoses. When endeavouring lo prepare lactose from galactose and glucose by 



