The last column in the above tables or the proportional amount of tannin is arrived at in the following manner. I first calculate the average amount of alkaloid in tea as consumed on a basis of the above figures. Thus the average amount of alkaloid in Indian teas as seen in Table H calculates out to 2·84 per cent. This is multiplied by the proportion of Indian teas on the market, viz. about 60 per cent. in the same way the average Ceylon alkaloid 2·68 is multiplied by 30, and the China average 2·40 multiplied by 6. If we add these products together and divide by 60 + 30 + 6 = 96 this will give us the average percentage of alkaloid in tea as consumed and this amounts to about 2·8 per cent. The last column in Tables E, F and G, gives the proportion of tannin corresponding to 2·8 per cent. alkaloid; that is to say the tannin in each case is multiplied by 2·8 and divided by the amount of alkaloid actually present. This figure which represents the proportional amount of tannin present renders the comparison of the different teas possible so far as the astringent action is concerned. The following table summarises the results of analyses of the three classes of teas:-- TABLE H. Proportion of Tannin Class of Number of Per cent. Per cent. Per cent. corresponding Teas. Analyses. Extract. Alkaloid. Tannin. to 2·8 per cent. Alkaloid. Indian Teas 18 26·11 2·84 7·43 7·32 Ceylon Teas 12 26·04 2·68 7·85 8·20 China Teas 13 22·12 2·40 6·08 7·09