250 



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



Miscellaneous. 

 (Names of Donors are in Italics.) 



Chambers, E., F.K.S.— Cyclopcedia : or an Universal Dictionary 

 of Arts and Sciences, 4 vols. Folio, London, 1786. 



Hon. Sec. F. R. Kyngdon. 



Lockwood, Prof. Samuel, Ph.D. — Raising Diatoms in the 



Laboratory. The Author. 



"The Illustrated Sydney News," Vol. XXIV., No. 10, 



October 15th, 1887. The Proprietors, Sydney. 



" The South Australian Register,'" 5 October, 1887, containing 

 Eeport of the Annual Meeting of the Royal Society 

 of South Australia, 4 Oct., 1887. JR. T. Hall. 



te Triibner's American, European, and Oriental Literary Record," 



New Series, Vol. VIIL, No. 3, 1887. The Proprietors. 



Warren, Professor W. H., M.I.C.E.— The Strength and 

 Elasticity of New South Wales Timbers of Com- 

 mercial Value. The Author 



SOME NEW SOUTH WALES TAN-SUBSTANCES. 



Part IV.- — Leaves only. 



By J. H. Maiden, F.R.G.S., Curator of the Technological Museum, 



Sydney. 



[Read before the Royal Society of N.S.W. , December 7, 1887. .] 



Notes — (Third Supplement). 



1. It has been quite an oversight on my part that I have 

 omitted to state that all the determinations of tannic acid detailed 

 by me in the present (1887) Journal of this Society, have been 

 made by Fleck's process. The tannate of copper has in all cases 

 been reduced to cupric oxide, and Eeler's factor (1-3061) has been 

 employed to calculate the tannic acid. Eleck's acetate of copper 

 and ammonium carbonate process has been frequently used by me 

 during the last few years with very satisfactory results. Even 

 Procter, who has subjected the various processes for the estimation 

 of tannin, to as rigid a scrutiny as any chemist with whose 

 writings I am acquainted, does not impugn the accuracy of the 

 method, so far as I am aware. Being a gravimetric process it is 

 tedious, but considerations of this nature have had no weight with 



