The Navigation Acts, in effect, gave a monopoly of colonial commerce to
British ships. No trade could be carried on between Great Britain and
her dominions save in vessels built and manned by British subjects. No
European goods could be brought to America save in the ships of the
country that produced them or in English ships. These laws, which were
almost fatal to Dutch shipping in America, fell with severity upon the
colonists, compelling them to pay higher freight rates. The adverse
effect, however, was short-lived, for the measures stimulated
shipbuilding in the colonies, where the abundance of raw materials gave
the master builders of America an advantage over those of the mother
country. Thus the colonists in the end profited from the restrictive
policy written into the Navigation Acts.

_The Acts against Manufactures._--The second group of laws was
deliberately aimed to prevent colonial industries from competing too
sharply with those of England. Among the earliest of these measures may
be counted the Woolen Act of 1699, forbidding the exportation of woolen
goods from the colonies and even the woolen trade between towns and
colonies. When Parliament learned, as the result of an inquiry, that New
England and New York were making thousands of hats a year and sending
large numbers annually to the Southern colonies and to Ireland, Spain,
and Portugal, it enacted in 1732 a law declaring that "no hats or felts,
dyed or undyed, finished or unfinished" should be "put upon any vessel
or laden upon any horse or cart with intent to export to any place
whatever." The effect of this measure upon the hat industry was almost
ruinous. A few years later a similar blow was given to the iron
industry. By an act of 1750, pig and bar iron from the colonies were
given free entry to England to encourage the production of the raw
material; but at the same time the law provided that "no mill or other
engine for slitting or rolling of iron, no plating forge to work with a