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of appropriate solvents. Chevalier Claussen patented plans for 
the use of boiling alkaline solutions, and proposed to reduce 
the time to twelve or twenty hours for " retting" the flax 
chemically. An inspection of the diagrams shows the modes 
of stocking the vats, steam power, and the general arrangement 
of a "rettery" on Schenck's patent process ; and having seen, 
perhaps, the best in Ireland and England, I may speak of the 
elegant arrangement, and the completeness of the process to 
the careful observer, while the improvement in the atmos- 
phere and the precision of machinery and premises offer a 
complete contrast of business, skill, and capital, to the slow, 
wasteful, and pernicious plans of old. 
The introduction of the thermometer, and constant obser- 
vation, will do much to create the true men for work. The 
steam is allowed to enter at temperatures from 80° to 90°, and 
so delicate is this flax plant, and the whole process, that it is 
not yet decided what is the precise degree of heat that is best, 
whether 80°, or below it. Much depends, perhaps, upon the 
crop, the atmospheric changes, and whether the vessels are 
covered or not : the ultimate uses of the flax are also to be 
regarded. Again, some persons steep once and some twice ; 
some wash the flax, after steep, with clear water ; others 
remove with the supernatant fluid adhering : then in the 
drying, some dry rapidly under cover, others spread out to 
light and air, on the grass. 
There is no doubt that a peculiar fermentation is set up in 
these vats or vessels. After the process has been carried on 
in the vats, and the water allowed to cool, a peculiar scum 
has been observed, a sort of dusky film, which spreads upon 
the surface of the fluid. 
Professor Allman has minutely attended to the changes 
that take place, and, with the aid of the microscope, finds 
that when the flax and water are raised to 90° in a few hours, 
the liquid becomes of an amber colour, minute organisms 
