The function of the flour is not known, but it is the custom of the country people and, according to Cobbett, it is doubtless of some use. Alternately, place the gallon container at the bottom of the tun-tub and pour the wort into it, effectively mixing the yeast mixture. If the beer is not cold it will be 'foxed', having a bad taste. A quarter is a measure of grain equal to eight bushels. In the essay he gives examples of bushels of malt weighing 36 and 45 pounds per bushel.
Treacle is molasses.
If anything, treacle may be cooked a bit. Treacle candy is made by cooking molasses to the hard crack stage. To make a note on the economy of the time, Cobbett states that barley costs 2 shillings eightpence a bushel, malt eight shillings per bushel, and the very best hops only a shilling per pound. Thus, the cost of the above batch of ale and small beer cost less than a pound. The cost of a years worth of tea, poison to the body and soul that it is, he gives at 11 pounds 7s 2d, including lost worktime, the cost of fires and money lost by going to the public house to buy it.