WATTLES AND WATTLE-BARKS. 
The preparation of extracts causes an immense saving in freight, but an 
extract is chiefly valuable in that it enables us to utilize everything. The 
following is an account of a process as carried on in South Australia a few 
years backhand is suggestive : — kt Messrs. Barrow and Havcroft have estab¬ 
lished, at Echunga, a manufactory of tannage, which, from the methods 
employed, is almost pharmaceutical. About 10,000 tons of wattle-bark are 
sent annually from South Australia alone, and it is calculated that the waste 
in stripping is about four times this amount. The new factory converts the 
branches, too small to pay for stripping, into a strong fluid extract called 
tannage, which contains water GO per cent., and soluble tannin 38*2 per cent., 
according to an analysis by Mr. G. II. Hodgson of samples from the first 
80 tons recently shipped to England. i The wattle 4 trash’ yields 12 to 10 per 
cent, of tannage. Two men can often cut and load 5 tons, and the waggons 
can bring in two loads a day, equal to 5 or G tons ; and at the price (£1 a 
ton) which the firm is paying for thinnings and tops and branches, so much 
is offering that the patentees are obliged to distribute their order. The trash 
is tied up in large bundles and carted into the factorv. It is there weighed, 
close beside the machine which cuts it up into ‘chaff.’ This machine is very 
much like an ordinary steam-plane, the chisels revolving at a high speed, and 
cutting through 2i-inch saplings quite readily. The chips are shovelled 
into large wooden hoppers, into which steam is introduced from a largo 
Cornish boiler. There are three steam-heated vats, and the liquor is trans¬ 
ferred from one to the other, pumped into elevated tanks, and thence allowed 
to flow from a tap on to steam-heated evaporating pans, about 30 or 40 feet 
in length. The evaporation is so rapid that in traversing the pans from the 
one end to the other the liquid is converted into a thick, tenacious, treacly 
extract. At the end of the pans it flows into a cistern, and thence by a kind 
of treacle-gate into the casks, each of which will hold about 10 cwt. All 
that now remains to bo done is paste on a label, put in a bung, weigh the 
cask, and send it off to market. In the process of evaporation a certain 
portion of the tannic acid is destroyed. The plant can be easily moved from 
place to place. It does not pay to cart the trash far, but a few square miles 
of wattle country will keep a factory going. The utilization of thinnings 
allows the cultivation of the tree thickly on waste ground, and to begin 
cutting the third year. European tanners are quite accustomed to the use 
of such extracts, but it is said that it will be very hard to introduce it into 
the colonial tanneries .” — (Chemist and Druggist, 188G.) 
I believe that these works are now working with diminished output, 
as the extract was found to contain too much mucilage, and therefore did not 
find favour with the tanners. Wattles are rich in gum and mucilage, and 
some cheap process, which will get rid of these substances and leave the 
tannic acid uninjured, is a desideratum. 
The preparation of wattle-bark extract is no new tbiim. 
o 
“ The first shipment of tanning was made from Sydney to England as far 
back as 1823. in the shape of ail extract of the bark of two species of mimosa 
(Acacia), which was readily purchased by the tanners at the rate of £50 per 
ton. One ton of bark bad produced 4 cwt. of extract of the consistency 
of tar. 45 ' 
“In 181-3, 3,078 tons of mimosa bark were shipped from Port Phillip to 
Great Britain. The price then realized in the London market was £12 to 
*See P er “ On the Export and Consumption of Wattle-bark, and the process of 
Tanning, by James Mitchell (Troc. R.S. Van Diemen's Land , 1851). The subject of 
Extracts is here dealt with. 
