from
Bouvier's Law Dictionary, Revised 6th Ed (1856)
TOUR D'ECHELLE, French law. Tour d'echelle is a right which the owner of an
estate has of placing ladders on his neighbor's property to facilitate the
reparation of a party wall, or of buildings which are supported by that
wall. It is a species of servitude. Lois des Bat. part 1, c. 3, sect. 2,
art. 9, Sec. 1.
2. In another sense by this term, or echellage, is understood the space
of ground left unoccupied around a building for the purpose of enabling the
owner to repair it with convenience; this is not a servitude, but an actual
corporeal property. Td. part 1, c. 3, sect. 2, art. 9, Sec. 2.