The result came to be that for several hundred years, embracing the whole colonial period, England had two distinct sets of courts, acting under different rules, and each trying a different kind of cases. Those involving questions of trust, account, fraud, mistake or accident, were the principal subjects of equitable jurisdiction. Equity also could prevent wrongs, while law could only punish them.[Footnote: See Chap. XX.] It was not, however, always easy to mark the line between cases, and say which belonged in the common law tribunals and which in those of chancery. Many an action failed, not because there was no just cause of action, but because it had been brought in the wrong court. In the American colonies, and for many years in the States which succeeded them, these distinctions of procedure were generally observed.[Footnote: In Pennsylvania the courts largely disregarded them and asserted that equity was a part of its common law. See Myers _v._ South Bethlehem, 149 Pennsylvania State Reports, 85, 24 Atlantic Reporter, 280.] In some there were, in some there still are, separate courts of equity held by a Chancellor, aided, if necessary, by Vice-Chancellors. In others two dockets or lists of cases were (and in a number of them still are) kept in the same court, and the same judge disposed of those on one docket as a court of equity and of those on the other as a court of law. Such a system is intrinsically absurd. It has been maintained by whatever States yet tolerate it for two reasons: because the lawyers and the community are used to it, and because it furnishes a convenient test of any claim of right to a jury trial. All our State Constitutions have some provision for maintaining such rights, but they do not define the cases in which the right exists. That is left to the courts, and their rule is that it cannot be claimed in cases that call for equitable as distinguished from legal relief. In most of our States and Territories legal and equitable causes of action or defenses may now be joined, and legal and equitable relief given in one suit. This reform in procedure was largely due to the labors of David Dudley Field, and became general throughout the country during the last half of the nineteenth century. The result has been that separate courts of equity are now to be found only in a few States.