ON SOME N.S.W. TAN-SUBSTANCES. 273 



A. binervata, sometimes so dense that he has some difficulty in 

 making his hides sink in it. He also points out that the tannin 

 of A. binervata is more quickly extracted by water than that of 

 A. decurrens, and that the liquor obtained is quicker and sharper 

 in its action than that from A. decurrens ; he finds A. decurrens 

 better adapted for heavy leather such as sole and mill-belt, but 

 not so well for lighter work, — uppers, <fcc., for which he prefers 

 A. binervata. 



92. Acacia binervata, DC. Compare Proc. R. S., N.S.W., 

 xxi., 90. See also A. decurrens (No. 91 this paper). 



Sample from Tomerong, near Jervis Bay, between Nowra and 

 Milton. Collected end of February, 1888. Analysed 14th to 

 15th September, 1888. 



As received, this sample had received its first crushing in the 

 mill. Nevertheless it was possible to pick samples showing a 

 fair proportion of inner and outer bark. The outer bark is 

 somewhat scaly, and the inner bark is of a light reddish-brown 

 and very fibrous. Colour of dry powder, pale orange-brown, with 

 much fibre. This bark cannot be mistaken for A. decurrens, 

 owing to its fibrous nature. 



Extract — 37*8 per cent. Colour, bright ruby ; of moist residue, 

 very dark Sienna brown. 



Tannic acid — 19*301 per cent. Non-tannin and impurities — 

 2*032 per cent. 



Mr. Shepherd states that many years ago he was employed in 

 a tan-yard in which " Ironbark " (Eucalyptus siderophloia or E. 

 leucoxylon) was used for tan-bark. The process of tanning went 

 on satisfactorily, but in the end the leather assumed a " bloom," 

 which did not take the market, although he believes the leather 

 itself was not inferior in quality. He also remarks that working 

 with Eucalyptus bark had the advantage over Acacia bark in 

 that when hides were tanned too hard, part of the tannin could 

 be removed and the hides rendered softer ; A. binervata bark 

 permits this to a slight degree, but not A. decurrens. 



Although in these papers I have not touched upon the " liming 

 process," nor upon any of the tanning processes, the following 

 note is interesting : — Mr. Shepherd's experience with lime is that 

 he can always depend upon shell-lime to obtain uniform results, 

 whereas he cannot depend upon stone-lime, as by the use of the 

 latter article the hides sometimes come out a dirty brown or 

 rusty colour. 



B— October 3, 1888. 



