=========+==========+====+====+====+====+====+====+====+==== Per cent.| | | | | | | | | PbO | |0.05|0.10|0.30|0.50|0.70|1.00|1.30|1.60 ---------+----------+----+----+----+----+----+----+----+---- | { 1 day | -- |0.07|0.63|1.34|1.05|1.53|0.93|1.35 | { 3 days| -- |0.07|3.52|4.31|2.75|4.86|4.82|4.12 Per ct. | { 5 days| -- |0.09|5.04|6.06|6.09|6.75|6.66|5.52 gain | { 12 days| -- | -- |6.88|7.54|7.43|7.76|7.32|6.47 | { 15 days| -- | -- |8.84|8.93|8.59|8.81|8.44|7.46 | { 20 days|0.05|0.20|9.02|9.08|8.90|9.03|8.65|7.83 ---------+----------+----+----+----+----+----+----+----+---- SOYA BEAN OIL AND MANGANESE DRIER -----------------+----------+----+----+----+----+---- Per cent. MnO_{2}| |0.01|0.05|0.15|0.26|0.30 -----------------+----------+----+----+----+----+---- | { 1 day | -- | -- |0.02|0.02|0.01 Per ct. gain | { 10 days| -- |5.06|6.48|6.10|5.97 | { 20 days|0.05|9.07|8.80|6.78|6.51 -----------------+----------+----+----+----+----+---- SOYA BEAN OIL, MANGANESE AND LEAD DRIER -------------+----------+----+----+---- Per cent. PbO| |0.20|0.30|0.50 -------------+----------+----+----+---- MnO_{2} | |0.05|0.15|0.25 -------------+----------+----+----+---- | { 1 day |3.04|3.77|3.74 Per ct. gain | { 8 days|5.96|6.43|6.47 | { 12 days|6.33|6.78|6.67 =============+==========+====+====+==== =Tung Oil.= There are grown in China and Japan many varieties of the "aleurites cordata," popularly known as the tung tree. This tree bears great quantities of large sized nuts containing as high as 40% of an oil which yields itself in a viscous yellow form upon heating and crushing of the fruit. The raw oil, which chemically consists of the glycerides of oleic, oleo-margaric, and probably isomeric acids, is distinguished by its rapid drying properties. When spread in a thin layer it produces a hard film with an opaque frosted surface, often showing a tendency to wrinkle. Treated tung oil will dry to a clear, water-shedding, elastic film. This oil is made by heating the raw tung oil at a comparatively low temperature with other oils and a metallic drier such as litharge. [Illustration: _Photographs courtesy of David Fairchild_ Aleurites Cordata (Chinese Wood Oil) Barrel Factory at Cooperage Shop] [Illustration: _Photographs courtesy of David Fairchild_ Aleurites Fordii (Chinese Wood Oil) Fruit from trees at the end of fourth year] The affinity of tung oil for rosin has resulted in the production of a series of moderate-priced varnishes most suitable for use in floor and deck paints or wherever great hardness is required. These varnishes are also finding application in the manufacture of concrete, steel, and flat wall paints; being especially suitable for the above purposes when compounded with kauri gum japan.