Mettler Toledo XS Série Mode D'emploi page 11

Density determination kit for XS balances
11
Suspend the sinker (10) from the bracket and ensure that it does not
touch either the beaker or the thermometer.
Tare the balance.
Add the liquid whose density you wish to determine to the beaker
(up to approx. 1 cm above the suspension eye of the sinker). Ensure
that no air bubbles adhere to the sinker (remove any air bubbles
with a fine brush).
Wait until the weight display of the balance is stable (stability
detector fades) and note the displayed value P (Weight of displaced
liquid).
Now determine the density ρ of the liquid (at the tempertature read
off on the thermometer), according to the preceding formula
(Section 5.1).