The reform was directly related to the great reform movement in England of the second quarter of the nineteenth century, and is a brilliant example of the application of the deductive method in politics. Sir Rowland Hill was a member of a Radical family, remarkable even in those days for its zeal for reform. It was the ambition of all members of the family to aid as far as possible the great movement; and all the brothers interested themselves in the study of social and economic questions, with a view to reform and improvement.[67] In the year 1835 there was a large surplus of revenue, and the brothers speculated on the direction in which reduction of taxation might best be made.[68] Sir Rowland Hill examined carefully the results of the financial reforms which had been introduced in recent years, and found that the effect on the revenue of reductions in the rate of tax showed very considerable variations. While in some cases, as, for example, leather and soap, a reduction of the duty by one-half had reduced the revenue by one-third, a similar reduction of the duty on coffee had increased the revenue by one-half. From this Sir Rowland Hill concluded that it was of the utmost importance to select carefully the taxes to be reduced, and he cast about for some guiding principle in the light of which the most suitable tax for reduction might be discovered. This principle he deduced to be as follows, viz. that the tax which most called for reduction was that which had failed most to keep pace with the increasing numbers and prosperity of the nation.[69] Tested in this way, the tax on letters proved unsatisfactory. While in most other departments of the revenue the preceding twenty years had been years of expansion and progress--as might be anticipated during a period of peace following great and exhausting wars--in the case of the Post Office the period had been one of stagnation.