That the use of varnish sealing coats is not the proper procedure in the painting of plaster walls.
The Pittsburgh Plate Glass Company has always recognized and maintained the correctness of the principle of oil base wall paints and oil base primers.
LSVR
Uneven suction effects on poor walls may be generally counteracted by the use of varnish type priming coats – at
the risk of cracking and peeling of later paint coats.