XI, A, 6 



Gana: Some Philippine Tanbarks 



263 



The reactions of the infusions with some reagents indicate 

 that the extracts of pine and palo maria are similar in quality, 

 notwithstanding the difference in quantitative analysis. The 

 same qualitative similarity is found in the extracts of narra and 

 pili barks. The qualitative tests are given in Table II. The 

 action of the various infusions on delimed sheep skin is shown 

 in Table III. 



Table II. — Reactions of the infzision of the barks with reagents. 



Bark. 



Reagent. 



Concentrated 

 sulphuric acid. 



Boiling diluted sul- 

 phuric acid. 



Bromine water. 



Ammonium ferric 

 alum. 





Liquid. 



Precipitate. 



Precipitate. 



Precipitate. 



Pine - 



Yellowish 



Reddish orange; 



Brown . 



Greenish black. 





brown or vio- 



difficultly soluble 









let. 



in alcohol and in 

 boiling water. 







Narra -_..._ 



Yellowish 



Red; soluble in al- 



do 



Reddish black or 





brown. 



cohol and in boil- 

 ing water. 





black with violet 

 tinge. 



Palo maria 



Brown 



Red- difficultly sol- 



do 



Greenish black. 







uble in alcohol 











and in boiling 











water. 







Alibangbang __ 







Whitish 



Greenish brown. 



Pili 



Yellowish 



Reddish brown; sol- 



Brownish yel- 



Brownish black or 





brown. 



uble in alcohol 

 and in boiling 

 water. 



low. 



very dark brown 

 with violet tinge. 



Oak 



do 



Red; difficultly sol- 

 uble in alcohol 



. do 



Green to bluish 

 black. 













and in boiling 











water. 







Table III. — Tanning effects of infusions of Philippine barks on delimed 



sheep skin. 



Bark. 



Leather produced. 



Pine 



Satisfactory leather, of reddish tan, with firm texture and good grain. 

 Tanning is slow. 



Satisfactory leather, nut brown, with full, firm texture and good grain. 



Satisfactory leather, similar to pine-tanned leather in color, texture, and 

 grain. 



Satisfactory leather; yellowish brown, firm texture, and good grain. Tan- 

 ning is slow. 



Light reddish brown leather, somewhat loose in texture and harsh in grain. 



Narra _ _ 



Palo maria 



Pili 



Oak-_. -,.. 





