UKXKltA L 01 >KRA Y7OA',S'

matter and has prescribed1 rules for the construction ami use of
all volumetric apparatus. Home of the more important feat urns
of these specifications are given below. Kvery good laboratory
should prescribe* that apparatus shall conform to these specifi-
cations wherever possible and upon receipt of tbe various pieces
they should be calibrated, in order to establish any n<w\ssary
corrections in the graduations.

Specifications, ....... -The unit of volume is the true liter. This is

defined as the, volume occupied bij one kilogram of /;///'<; //vi/w nt
4°. The standard working temperature is 20°.

Inscriptions."- ..... - Kvery instrument must bear a legend indicating
the capacity in liters or millilifers (the latter is almost identical
with cubic centimeters), the temperature at which it is to be used
and whether to contain or to deliver the stated amount. Bore! ten
and pipettes must bear a statement as in the timo required for
unrestricted outflow of the full quantity of water.

Special dimensions are given for each class of instrument.

The time of outflow i.s specified as follows: Pipettes having a
single graduation ("transfer'* pipetten) must have tbe tip of
such sixe that the time of free* outflow Js not more* than 1 minute
nor less than the following, according to the sisse of the pipette:

Capacity (in <•<•) up to urn!
Minimum outflow tirn«* (in «er.;

JO
2(1

50

Burettes must empty in not more than <f minutes nor

than as indicated below.

L ••— RATK

Hi

Mtnirntirit timi*

flf (rtlillljW, MIT.

Mtntitittttt ftiiii*
of <Hitftow, ««***,

70
60

50
45

140

120

HM5

ttO

HO

m

30

25
20

If*

40
»5
30

tif