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active and required more attention and also the application 
of lime occasionally to regulate the process with the same 
kind of judgment as used in the blue dying Woad vat— 
When the heat increases too rapidly, turning is indispensa¬ 
bly necessary, and the application of very fine flour lime 
regularly strewed over every laying of them ; or if the 
couch is getting too dry, lime water instead of common wa¬ 
ter applied by a gardener’s watering pot may have an equal 
effect without loading the Woad with the gross matter of 
the lime ; though I conceive the gross dry flour lime and 
the oxygen in the air furnish more carbonic acid gas to 
the Woad, and retain such principles as are essential to a 
better effect 
I have experienced that that Woad which requires the 
most lime to preserve a temperate degree of fermentation 
and takes most time, is best, so that at length it comes to 
that heat which is indispensable tp the production of good 
Woad. 
In this Gouch it is always particularly nepessary to secure 
the surface as soon as the leaves begin to be reduced to 
a paste by rendering it as smooth as possible and free 
from cracks ; this prevents the escape of much carbonic 
acid gas (which is furnished by the lime and the fermenta¬ 
tion) and also preserves it from the fly, maggots and worms 
which often are seen in those parts where the heat is not so 
great or the lime in sufficient quantity to destroy them ; it 
is surprising to observe what a degree of heat they will 
bear. This attention to rendering the surface pf the couch 
even and compact, is equally necessary in either pro¬ 
cess, and to turning the Woad as a dung heap exactly, dig¬ 
ging perpendicularly to the bottom. The couching house 
should have an even floor of stone or brick and the walls 
the same, and every part of the couch of Woad should be 
beaten with a shovel and trodden to render it as compact a$ 
possible. 
The grower of Woad should erect a long shed in the 
