This section is from the book "The Law Of Real Property and Other Interests In Land", by Herbert Thorn Dike Tiffany. Also available from Amazon: A Treatise on the Modern Law of Real Property and Other Interests in Land .
Equitable powers are of two kinds. The first kind consists of powers of appointment, similar to those of the class last described, except that they are exercisable only with reference to equitable interests in the land, the legal title being outstanding in trustees, and not within the purview of the power. Thus, the legal fee may be vested by conveyance or devise in trustees for A for life, with remainder in trust for such persons as A shall appoint, and, in default of appointment, in trust for B in fee simple, in which case the exercise by A of the power in favor of C will divest the equitable interest of B in favor of C, without, however, affecting the legal ownership in the trustees, except that they will, in equity, be compelled to hold for the benefit of C.21
Another kind of equitable power, and one which is of frequent occurrence, exists when the legal owner, holding for the benefit of another, is given power to sell or lease or otherwise create estates or interests riod between the creation of the power and the making of the appointment,29 and the dower claim of the wife of the person entitled in default of appointment may likewise be defeated by the making of the appointment.30
20. See. Whitby v. Mitchell, 42
Oh. Div. 494; Security Trust &
Safe Dep. Co. v. Ward, 10 Del..Ch.
408, 93 Atl. 385.
21, Sugden, Powers, 200; Far-well, Powers (3rd Ed.), 3.