364 
Also from this table it appears, that, in contrast with what was 
always found for glucose, the galactose was not totally retained in 
any of the experiments, and further, that the retaimed part forms 
more or less the half — here a little less than the half. 
Consequently the first explanation mentioned on page 361 fails here 
and we are obliged, per exclusionem, to accept the second expla- 
nation, viz., the one based upon the fact that in aqueous solution 
the galactose exists in two modifications. 
2. The solution of galactose contains two forms of galactose 
that behave differently towards the kidneys. 
As is known a large number of sugars exhibits multirotation 
(DuBRUNFAUT), i.e. some time after the preparation of the aqueous 
solution they generally possess a slighter specifie rotation than 
immediately after the solution is made. Several explanations, which 
we need not discuss here have been given for this. It is agreed upon 
however that under the influence of the solvent, part of the sugar 
changes into another form with a slighter rotatory power. The two 
forms are in equilibrium. 
This idea is based, in the first place, upon the researches of 
Tanret’), who separated in solutions, first of glucose and afterwards 
of galactose and other sugars, three forms with different rotatory 
power, and several different physical properties; these he termed 
a, B and y: the « modification of d-galactose with a specific rotatory 
power of + 135°, a 3 modification with [¢]p>=-+ 81° and a y 
modification of [a|p = + 58°. 
More extensive researches, especially of E. Roux’) and further 
of BourqueLor®) have taught however that the 8 variety of TANRET 
is no independent sugar, but consists of a mixture of « and y, which 
are in equilibrium. 
I find it useful to point out here a misunderstanding in the literature 
which has given me much trouble personally, and, I am informed, 
others also. in several scientific treaties and textbooks it is stated 
or taken for granted that there are two modifications only; these 
are called then the @ and 3 modifications. It is clear here that the 
8 modification is actually the y modification of Tanrer. But, as far 
/ 
as | know, nobody ealls attention to this fact. To what faulty reports 
1) Tanret, Bulletin de la Société Chimique, [3], 13, (1895), p. 728 [3], 16. 
(1896), 195. 
2) E. Roux, Ann. Chim. et de Phys., VII Série, 30, p. 422. 
3) Bourquetot, Journal de Pharm. et de Chem. [7], 14, (1916) 225. 
