Jewish settlers were indeed to be found in many of the Dutch towns; and it was through them that Holland became famous in 17th century Europe for the perfection of her goldsmiths' and silversmiths' art and for jewelry of every kind.

Another industry, which had its centre at Delft, was that of the celebrated pottery and tiles known as "delfware." It will be evident from what has been said above that vast wealth flowed into Holland at this period of her history, but, as so often happens, this sudden growth of riches had a tendency to accumulate in the hands of a minority of the people, with the inevitable consequence, on the one hand, of the widening of the gulf which divided poverty from opulence; on the other, with the creation among rich and poor alike of a consuming eagerness and passion for gain, if not by legitimate means, then by wild speculation or corrupt venality.

Bubble companies came into existence, only to bring disaster on those who rashly invested their money in them.

The fever of speculation rose to its height in the mania for the growing of bulbs and more especially of tulips, which more and more absorbed the attention of the public in Holland in the years 1633-6.

Perfectly inordinate sums were offered in advance for growing crops or for particular bulbs; most of the transactions being purely paper speculations, a gambling in futures.