the so-called ãcancellous tissue.ã The older anatomists were content to describe this cancellous tissue as a sort of ãspongy network,ã or irregular honeycomb, until, some fifty years ago, a remarkable discovery was made regarding it. It was found by Hermann Meyer (and afterwards shewn in greater detail by Julius Wolff and others) that the trabeculae, as seen in a longitudinal section of a long bone, were arranged in a very definite and orderly way; in the femur, they spread in beautiful curving {682} lines from the head to the tubular shaft of the bone, and these bundles of lines were crossed by others, with so nice a regularity of arrangement that each intercrossing was as nearly as possible an orthogonal one: that is to say, the one set of fibres crossed the other everywhere at right angles. A great engineer, Professor Culmann of Zû¥rich (to whom, by the way, we owe the whole modern method of ãgraphic staticsã), happened to see some of Meyerãs drawings and preparations, and he recognised in a moment that in the arrangement of the trabeculae we had