THE 



NEW-ENGLAND 

 FARraEBSMND MECHANICS' JOURNAL. 



Vol. I. GARDINER, NOVEx^BER, 1838. N... 11. 



IVCECHAIflCS. 



For the Fanners' and Mechanics' Journal. 



Specification of the Patent granted to Wm. Coburn, for a Method 

 of Extracting Tannin from Bark, ^c, by Steam. 



To all persons to whom these presents shall come, William 

 Coburn, of Gardiner, in the County of Kennebec, and State 

 of Maine, Currier, sends greeting : — 



Be it known, that 1, the said WilHam Coburn, have invented, 

 constructed and applied a new and useful improvement in the 

 mode of applying sienni for extracting tannin and other ingredients 

 contained in Hemlock, Oak, or any other Bark, or from the leaves 

 and branches of sumach, oak, or chestnut, or from any other-sub- 

 stance usually used in the tanning or manufacturing of skins into 

 leather. 



This improvement consists in applying steam to the substance 

 from which tannin is to be obtained, in the following manner : viz. 

 The steam is conveyed from the boiler, by a tube into the lower 

 part of a cistern or tub. The tub, or vessel used for that purpose, 

 is furnished with a false bottom perforated with holes, and raised a 

 few inches from the true bottom. The tub is tilled with the sub- 

 stance to be acted upon by the steam, which is suffered to pass 

 into the tub between the bottom. Cold water, or bark liquor, is 

 then occasionally poured into the top of the tub, and the liquor 

 thus obtained is drawn ofT by means of a cock placed between the 

 bottoms of the tub. The advantages of this mode are, 



1st. The simplicity of the apparatus necessary for the applica- 

 tion of the steam ; no pressure is required to confine the steam in 

 the tub, other than the weight of the materials acted upon. 



2d. By the application of cold bark water, or liquor, or cold 

 water, the steam is found to penetrate the substance much more 

 easily, and a greater quantity of tannin, &;c. is obtained. 



Gardiner, JVovember, 1828, 

 Mr. Editor, — By experiments in my mode of extracting tannin 

 as above described, 1 think that a saving of about one-third may 

 31 Vol. 1. 



