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PAINT TECHNOLOGY AND TESTS 



COMMITTEE U REPORT 1910 

 TABLE II. ANALYSIS OF AVERAGES. GRADE OF EXCELLENCE FROM 8 TO 10 



(Only resistance to corrosion was considered, and only pigments which were com- 

 mon to both tests are included) 



The writer has recently made a careful inspection of the panels 

 painted with single pigment paints, and has made the following 

 brief summary of the characteristic appearance of each. 



Panel No. i Dutch Process White Lead. The excessive 

 chalking which took place began to disappear at the end of a 

 year, being washed away by the rains and carried away by the 

 winds, so that there was left upon the surface but a thin coating 

 of pigment, insufficient to give good protection. Slight corro- 

 sion was apparent beneath the film. 



Panel No. 2 Quick Process White Lead. In the same 

 condition as Panel No. 1. 



Panel No. 3 Zinc Oxide. Panel covered with thin lateral 

 streaks of rust, due to the admittance of moisture in cracks 

 caused by brittleness of film. Result doubtless due to insuffi- 

 cient amount of oil used with pigment. Removal of film shows 

 steel very bright except where cracks have formed. 



Panel No. 4 Sublimed White Lead. Although sublimed 

 white lead chalked very heavily, the chalked pigment seemed to 



