| Do | 11.62 | 9.06 | 5.35 | 2.17 | 2.56 | |Pale ale | 11.04 | 9.50 | 5.43 | 2.03 | 1.54 | | Do | 11.88 | 9.63 | 5.67 | 2.09 | 2.25 | | Do | 11.75 | 9.11 | 5.53 | 2.12 | 2.64 | |Brown stout | 12.03 | 9.38 | 5.69 | 2.11 | 2.65 | | |-------+-------+--------+--------+----------+ | Average for ales | | | | 2.12 | 1.96 | | Average for beers and ales| | | | 2.13 | | +------------------------------+-------+-------+--------+--------+----------+ In Table V have been collected results (calculated from Tables I-IV) which show the loss in solids between the wort and the finished fermented product, the loss in sugar, the yield of alcohol, the loss in solids divided by the alcohol, and the difference between the loss in solids and the loss in sugar. By dividing alcohol into loss in solids there was secured a factor which makes possible the estimation of the solids in the original wort, provided that alcohol and extract are known. This factor also shows the yield of alcohol for a given amount of solids disappearing during fermentation. It has been found in the case of the beers that this factor averages 2.14, while in the case of the ales it averages 2.12, making an average for all of the products of 2.13. This clearly shows that in the yield of alcohol for a given amount of fermentable solids there is no appreciable difference between top fermentation products, such as ales, and bottom fermentation products, such as beers. A marked difference in loss in solids is shown, however, when we compare the beers with the ales. In the case of the beers we find there is practically no difference between the loss in solids and the loss in sugar, while in the case of the porters and ales there is a very appreciable difference. The difference between the loss in solids and the loss in sugar is only 0.04 per cent for all of the beers; while in the case of the porters and ales the difference varies from 1.47 per cent to 2.65 per cent, with an average of 1.96 per cent. These figures clearly show that in the case of the porters and ales there has been some material other than sugar fermented. Unfortunately, the determination of dextrin was not made in all of the worts, so that the actual decrease in dextrin can be shown only in a few cases. But in those cases where we have the actual results the difference between loss in solids and the loss in sugar compares very closely with the actual amount of dextrin disappearing during fermentation. DEVELOPMENT OF ACIDS DURING FERMENTATION.