524 IGLEHART v. ARMIGER.

as its incident. A bond, note, or mortgage may however be
executed as being, in itself, the creator, evidence, and incident of
a debt; but an equitable Hen cannot be thus made and executed
apart from, and independently of a contract of purchase, or as
being, in itself, the evidence of a purchase. Hence, it is perfectly
evident, that a bond, note, or mortgage may be, in itself, at once
the principal and incident; it may create a debt, and thus estab
lish the principal of which it is the evidence and incident; but an
equitable lien is so purely an incident, that it cannot be called into
existence in any other manner than as an attendant upon a contract
of purchase; and when that is satisfied or substantially waived,
the equitable lien is gone.

It is true, as a general rule, that the principal carries with it all
its incidents, but not the reverse. Accessorium non ducit, sed sequi-
tur suum principale.(g) And therefore if the debt be in any man-
ner distinctly and legally assigned; the assignment carries with it
the bond, note, or mortgage as its incident; because the transfer
of the money carries with it the mortgage interest in the land, and
all other securities which were given for the purpose of assuring
its payment. This may be done by parol notwithstanding the sta-
tute of frauds. So too, if it be the intent of the mortgagee to
give the debt only, he may do so by a will not attested by three
witnesses; and the legatee may in the name of the heir obtain, in
equity, all the benefit of the mortgage : but if his intention was to
devise it as land, then his will must be duly attested for that pur-
pose. The reason of this is, that a gift, assignment, or bequest
of the principal carries with it all its beneficial incidents.(h)
But an equitable lien is an encumbrance upon land, which can
only be held by a vendor; and although assets may be mar-
shalled, so as to put a vendor altogether upon his equitable lien,
for the benefit of other creditors, yet no third person can, as assignee
of the vendor, derive any benefit from such lien ;(i) nor can it, like
a bond or mortgage, be assigned; because it is not expressed in
writing, or in any separate contract; but exists only as an insepa-
rable equitable incident of the contract of purchase; and is raised
by construction of equity, in favour of the vendor only. To
allow it to pass by an assignment of the claim for the purchase

(g) Co. Litt 151,152; 2 Blac. Com. 176.—(A) Green v. Hart, 1 John. Rep. 580;
Jackson v. Willard, 4 John. Rep. 41; Runyan v. Mersereau, 11 John. Rep. 534;
Hartin v. Mowlin, 2 Burr. 978; Pow. Mort. 140,144, 266, 429.—(i) Mackroth v.
Symmons, 15 Ves. 339, note; Sug. Vend. & Pur. 395.