These averages look well, undoubtedly, for Mr Sadler's theory. The numbers 396, 390, 388, 378, follow each other very speciously in a descending order. But let our readers divide these thirty-four counties into two equal sets of seventeen counties each, and try whether the principle will then hold good. We have made this calculation, and we present them with the following result. The number of children to 100 marriages is-- In the seventeen counties of England in which there are from 100 to 177 people on the square mile..........387 In the seventeen counties in which there are from 177 to 282 people on the square mile..........389 The difference is small, but not smaller than differences which Mr Sadler has brought forward as proofs of his theory. We say that these English tables no more prove that fecundity increases with the population than that it diminishes with the population. The thirty-four counties which we have taken make up, at least four-fifths of the kingdom: and we see that, through those thirty-four counties, the phenomena are directly opposed to Mr Sadler's principle. That in the capital, and in great manufacturing towns, marriages are less prolific than in the open country, we admit, and Mr Malthus admits. But that any condensation of the population, short of that which injures all physical energies, will diminish the prolific powers of man, is, from these very tables of Mr Sadler, completely disproved. It is scarcely worth while to proceed with instances, after proofs so overwhelming as those which we have given. Yet we will show that Mr Sadler has formed his averages on the census of Prussia by an artifice exactly similar to that which we have already exposed. Demonstrating the Law of Population from the Censuses of Prussia at two several Periods. (Here follows a table showing for inhabitants on a square league the average number of births to each marriage from two different censuses.) 1756 1784 832 to 928...4.34 and 4.72 1175 to 1909...4.14 and 4.45 (including East Prussia at 1175) 2083 to 2700...3.84 and 4.24 3142 to 3461...3.65 and 4.08