| Color | Water White |
| Specific Gravity at 15° C. | .862-.875 |
| Boiling Point | About 156° C. |
| Distillation | 95% should distil between 153 and 165° C. |
| Residue on Evaporation | Not over 2% |
| Polymerization | Not over 5% should remain unpolymerized at end of half hour |
| Flash-Point | Over 40.5° C. |
| Spot Test | No grease spot should remain when dropped on paper and allowed to evaporate |
| Water | None |
Wood Turpentine. High-grade wood turpentine is now produced by the steam distillation of finely cut fat pine wood. The lower-grade qualities are often produced from the destructive distillation of sawdust, stumpage, etc., and these products, on account of their content of formaldehyde, are objectionable in odor. In the steam distillation process, however, a high quality product is obtained by cutting out the heavy fractions and redistilling the lower and purer fractions. It has a high oxidizing value, causing the rapid drying of paints and varnishes to which it has been added. Its solvent value is often greater than that of gum turpentine. When properly refined it has a sweet smell and is to be highly recommended.
Analyses of samples of pure wood turpentine which have come to the writer for examination follow:
| No. 1 | No. 2 | |
| Sp. Gr. at 15° C. | .862 | .862 |
| Boiling Point | 158° C. | 162° C. |
| Distillation: 95% distils between | 158 and 185° C. | 162 and 177° C. |
| Residue on Evaporation | 1.03% | 3.06% |
| Polymerization Test | 4.1% remains unpoly- merized at end of 1⁄2 hour | 0.1 cc. out of 6 cc. unpolymerized = 1.66% |
| Spot Test | No grease spot on evap- oration | No grease spot on evap- oration |
| Odor | Excellent | Not objectionable |
| Color | Water White | Water White |
| Flash Point | 47.6° C. |
Petroleum Spirits. There are produced from Texas crude oil which has an asphaltum base, and Pennsylvania crude oil which has a paraffin base, high boiling-point petroleum spirits which have come into wide use as paint and varnish thinners. When such materials have the proper evaporating value, high flash-point and freedom from sulphur, they are to be highly recommended as paint thinners. The following shows the analyses of a few of these materials examined in the writer’s laboratory:
Petroleum Spirits
| Texas Base | California Base | Penna. Base | |
| Color | Water White | White | Water White |
| Specific Gravity | .811 | .79 | .81 |
| Boiling Point | 156° C. | 138° C. | 146° C. |
| Flash-Point | 44° C. | 40.5° C. | 43° C. |
| Residue on Evaporation | .2 | .15 | .12 |
Benzol. “Solvent naphtha” or 160-degree benzol is a product obtained from the distillation of coal tar, differing from benzine, a product obtained from the distillation of petroleum. It is a valuable thinner to use in the reduction of paints for the priming of resinous lumber and refractory woods such as cypress and yellow pitch pine. The penetrating and solvent values of benzol are high, and it often furnishes a unison between paint and wood, that is a prime foundation to subsequent coatings, preventing the usual scaling and sap exudations which often appear on a painted surface. Because of the great solvent action of benzol, it should never be used in second and third coatings. The writer has successfully painted inferior grades of cypress with a paint containing benzol in the priming coat.
Benzine. Benzine is seldom used in paints on account of its rapid evaporation, which is apt to cause pinholing of films and other surface defects. In paints of the dipping type where rapid evaporation is essential, benzine finds its widest application.