i68
Harbour engineering.
siderable quantity of one stone has to be cut away in order to form the
joggle.1
JOGGLE JOINT DOWEL JOINT
□OVETAIL MASONRY
(PLAN.)
Flos. 137-141.—Masonry Joints and Connections.
Dovetailing is another method of bonding masonry, but it nécessitâtes
much elaboration in fitting and jointing, and therefore is costly. It has been
very often used for lighthouse work.
10 S 0 10 20 30 40 50
luuhl111 _I ____L----I----I---I
Scale of feet
Fia. 142. —Piano-blockwork at North Jetty, Tynemouth.
Somewhat similar, though perhaps less intricate, is the system of il piano”
bloeks used by Mr Messent in the construction of the Tyne breakwaters. The
1 The distinction between a dowel and a joggle is, however, not always observed, and
the terms are often treated as synonymous for either class of joint