REQUISITE CONSTANTS OF PURE GUM TURPENTINE Color Water White Specific Gravity at 15 deg. C. .862-.875 Boiling Point About 156 deg. C. Distillation 95% should distil between 153 and 165 deg. C. Residue on Evaporation Not over 2% Polymerization Not over 5% should remain unpolymerized at end of half hour Flash-Point Over 40.5 deg. 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 deg. C. |.862 |.862 Boiling Point |158 deg. C. |162 deg. C. Distillation: 95% | | distils between |158 and 185 deg. C. |162 and 177 deg. C. Residue on Evaporation|1.03% |3.06% Polymerization Test |4.1% remains unpolymerized|0.1 cc. out of 6 cc. |at end of 1/2 | unpolymerized = |hour | 1.66% Spot Test |No grease spot on |No grease spot on | evaporation | evaporation Odor |Excellent |Not objectionable Color |Water White |Water White Flash Point | |47.6 deg. C. ======================+==========================+====================