hese
acts were quickly disposed of in England. Three duty acts affecting
Negroes, including the prohibitory act, were in 1713 disallowed, and it
was directed that "the Dep^{ty} Gov^{r} Council and Assembly of
Pensilvania, be & they are hereby Strictly Enjoyned & required not to
permit the said Laws ... to be from henceforward put in Execution."[30]
The Assembly repealed these laws, but in 1715 passed another laying a
duty of L5, which was also eventually disallowed.[31] Other acts, the
provisions of which are not clear, were passed in 1720 and 1722,[32] and
in 1725-1726 the duty on Negroes was raised to the restrictive figure of
L10.[33] This duty, for some reason not apparent, was lowered to L2 in
1729,[34] but restored again in 1761.[35] A struggle occurred over this
last measure, the Friends petitioning for it, and the Philadelphia
merchants against it, declaring that "We, the subscribers, ever desirous
to extend the Trade of this Province, have seen, for some time past,
the many inconveniencys the Inhabitants have suffer'd for want of
Labourers and artificers, ... have for some time encouraged the
importation of Negroes;" they prayed therefore at least for a delay in
passing the measure.[36] The law, nevertheless, after much debate and
altercation with the governor, finally passed.

These repeated acts nearly stopped the trade, and the manumission or
sale of Negroes by the Friends decreased the number of slaves in the
province. The rising spirit of independence enabled the colony, in 1773,
to restore the prohibitive duty of L20 and make it perpetual.[37] After
the Revolution unpaid duties on slaves were collected and the slaves
registered,[38] and in 1780 an "Act for the gradual Abolition of
Slavery" was passed.[39] As there were probably at no time before the
war more than 11,000 slaves in Pennsylvania,[40] the task thus
accomplished was not so formidable as in many other States. As it was,
participation in the slave-trade outside the colony was not prohibited
until 1788.[41]

It seems probable that in the original Swedish settlements along the
Delaware slavery was prohibited.[42] This measure had, however, little
practical effect; for as soon as the Dutch got control the slave-trade
was opened, although, as it appears, to no large extent. After the fall
of the Dutch Delaware came into English hands. Not until 1775 do we find
any legislation on the slave-trade. In that year the colony attempted
to prohibit the im