work: a series of uprights is first set in position, and over this are
laid several horizontal courses of rather smaller stones. We must note
that the dry masonry which we are describing is still strictly
megalithic, as the blocks used are never small and often of enormous
size.

Buildings in which this system is used are occasionally roofed with
slabs, but more often corbelling is employed. At a certain height each
succeeding course in the wall begins to project inwards over the last,
so that the walls, as it were, lean together and finally meet to form a
false barrel-vault or a false dome, according as the structure is
rectangular or round. Occasionally, when the building was wide, it was
impossible to corbel the walls sufficiently to make them meet. In this
case they were corbelled as far as possible and the open space still
left was covered with long flat slabs.

It has often been commented on as a matter of wonder that a people
living in the stone age, or at the best possessing a few simple tools of
metal, should have been able to move and place in position such enormous
blocks of stone. With modern cranes and traction engines all would be
simple, but it might have been thought that in the stone age such
building would be impossible. Thus, for instance, in the 'temple' of
Hagiar Kim in Malta, there is one block of stone which measures 21 feet
by 9, and must weigh many tons. In reality there is little that is
marvellous in the moving and setting up of these blocks, for the tools
needed are ready to the hand of every savage; but there is something to
wonder at and to admire in the patience displayed and in the
organization necessary to carry out such vast pieces of labour. Great,
indeed, must have been the power of the cult which could combine the
force of hundreds and even thousands of individuals for long periods of