40 WOOD TURPENTINE. 



tively distilled turpentine (No. 4) leaving the least residue is the best 

 Another observer finds in striping that one destructively distille( 

 turpentine (No. 3) works like regular turpentine, while the steam 

 distilled (No. 1) and the destructively distilled turpentine leaving 

 the largest residue (No. 4) crack and crawl apart. This observatioi 

 does not appear to have been made by the other experimenters anc 

 would seem to be connected in some way with the pigment presen; 

 in the material used by this experimenter. It will be noted tha- 

 these are the samples that contain large percentages of heavy oiL 

 not distilling below 170 C. 



PIANO-RUBBING VARNISHES. 



One experimenter did not thin the varnishes, one thinned one gum- 

 turpentine varnish only, three thinned all varnishes alike, and twc 

 used different quantities of turpentine in thinning the varnishes. 



In some instances the varnishes thinned with the wood turpentine 

 remained tacky longer than the varnishes thinned with gum spirits 

 in others the reverse was true. In no case did the thinning agree 

 with the viscosity tests of the varnishes. The time of drying variec 

 but seemed to bear no relation to the kind of turpentine used in th< 

 varnish or to the viscosity of the original varnishes. In some 

 instances the wood turpentines were much slower than the gum 

 turpentines, while in others there was reported no practical difference 

 in this respect. 



With regard to luster, three found some difference among the var- 

 nishes. One reported that the steam-distilled wood turpentine 

 (No. 2) had the best luster, the destructively distilled (No. 3) being 

 second best. Another found one gum and one wood turpentine- 

 thinned varnish had medium gloss, and one gum and one wood 

 turpentine- thinned varnish had fair gloss. The other observers 

 distinguished no difference in this particular. One found that the 

 steam-distilled turpentine (No. 2) gave the best gloss, while one 

 gum (No. 1) and one destructively distilled product (No. 3) showed 

 tears. 



Two found the odor of all the wood turpentine objectionable; one 

 found the steam-distilled (No. 2) and one destructively distilled 

 (No. 4) objectionable. One found both destructively distilled sam- 

 ples objectionable, while another said that the No. 1 gum- turpentine 

 varnish had the odor of naphtha. 



No difference was detected in working qualities, except that one 

 observer found that the varnishes thinned with the destructively dis- 

 tilled turpentine (No. 3) worked unsatisfactorily. 



All rubbed down well, one observer reporting in favor of the gum 

 spirits. Three observers found no difference in behavior under the 

 brush, while two others found some difference. One reports sweating. 



