801 
c.c. of the amylum solution was added by means of a pipette. As 
a matter of course, all the tests of the same series were made with 
the same freshly prepared solution, which was obtained by mixing 
25 gr. of dried amylum with one liter cf water and heating it to 
the boiling point, while stirring the fluid and maintaining this tem- 
perature for about a minute. After cooling the mixture was made 
up to 2 liters *) and filtered through glass-wool or muslin. 
The flasks holding the phosphate-mixtures and the amylum, were 
first heated to 37° and then maintained at this temperature in the 
thermostat for at least 20 minutes previous to the addition of the 
enzyme. After the enzyme had been working an for 20 minutes, the 
flask was dipped into a boiling waterbath and was constantly and 
regularly moved, always in the same manner, till a temperature of 
90° was reached, so that every time the action of the enzyme was 
arrested in the same way. 
The reducing power of the cooled fluid was determined after 
BERTRAND and was expressed in m. Gr. copper per 100 cc. of the 
fluid. 
The determination of the reaction was performed electrometrically. 
The hydrogen-electrodes were treated after HasserBacH’s *) shaking 
method, and measured by means of mercury-calomel-electrodes with 
normal and '/,, n potassium chloride. The reaction is expressed in 
pu: the negative logarithm of the hydrogen-ions-concentration. 
The following tables show the results of the most important series 
of experiments. 
Ist Series of experiments. Enzyme v. T. 
Phos- 
| 
Nr, Phoricacid NaOH HO pe | Hek art Rotation (adineirench p 
| Solution MEER Ce ei Cr, il ae | m.Gr- minutes oh it 
ee harel 
Ekel | 13.4 26.6 200 AAD eee — 5.186 
2| 10 13.7 26.3 200 2: 18215 legs = 5.69 
Beene eis ae 200, | 2°) 212.30) | — 5.80 
Bio: 25 200 | 2 | 248.95} = ae 6.22 
S10 -).46 24° 200 Bi oyaegs, ee = 6.40 
6| 10 | 18 (22 | 200 | 2. | 176.50 Ren | = 6.78 
1) Occasionally 4 liters had to be made. 
*) Biochemische Zeitschrift, Bd. 30, p. 317. 
