Many municipal revolutions took place, and a large number of constitutional experiments were tried all over the country from the 13th century onward. Schemes which directed a gradual co-optation, two to choose four, these six to choose more, and so in widening circles from a centre of officialdom, found much favour throughout the Middle Ages. A plan, like the London plan, of two companies, alderman and council, was widely favoured in the 14th century, perhaps in imitation of the Houses of Lords and Commons. The mayor was sometimes styled the "sovereign" and was given many prerogatives. Great respect was paid to the "ancients," those, namely, who had already held municipal office. Not till the 15th century were orderly arrangements for counting "voices" arrived at in a few of the most highly developed towns, and these were used only in the small assemblies of the governing body, not in the large electoral assemblies of the people. In London in the 13th century there was a regular system for the admission of new members to the borough "franchise," which was at first regarded not as conferring any form of suffrage but as a means to secure a privileged position in the borough court and in the trade of the borough. Admission could be obtained by inheritance, by purchase or gift, in some places by marriage, and in London, at least from 1275, by a municipal register of apprenticeship. The new freeman in return for his privileges was bound to share with the other burgesses all the burdens of taxation, control, &c., which fell upon burgesses. Personal service was not always necessary, and in some towns there were many non- resident burgesses. When in later times admission to this freedom came to be used as means to secure the parliamentary franchise, the freedom of the borough was freely sold and given.