The varnish manufacturer can escape a great deal of annoyance and pecuniary losses if he personally looks after this part of his purchases or has someone whom he can rely on look after this end of the business. It is not sufficient to simply take a sample from the bunghole of a barrel on arrival, but each barrel should be well shaken up before a sample of the oil is taken. This precaution is necessary, because only the clear light colored tung oil is really fit for use in varnish. Dark and ill smelling tung oil is of little use in the manufacture of varnish. The situation has no doubt bettered itself of late years and our Chinese friends may have reformed or the European and American buyers at Chinese ports have compelled them to be more honest in their methods of bringing the oil to market. Certain it is that a great mass of tung oil, that was unfit for use, found its way into our markets. As the oil was always sold by weight it often happened that sand and earth, even water was found in the original packages. To keep out of trouble the consumer, be he varnish or paint manufacturer, must see that tung oil is free of moisture, which he can readily ascertain, for when the oil has been well shaken in the barrel or other container and is then still free from turbidity, it may be taken for granted that it is free from moisture. Moisture is mostly due to the presence of vegetable albumen and when the oil is boiled it will break at very low temperature, much of it going into the so-called foots that are of little value in paint manufacture and of none at all in varnish making. It is a fact generally recognized at the present time in the paint and varnish trade that raw tung oil cannot be employed in either paint or in varnish making, because of its tendency to dry unevenly in a shriveled film, and its further tendency to dry out flat and opaque in spots. There has been no end of experimenting during the past fifteen or twenty years and to show what has been done along these lines, the progress made and the present status is to be considered and described in the remainder of this chapter.