By a very simple calculation, based on the familiar principle of the parallelogram of forces, I gave to the apergic current a force and direction equivalent to a daily motion of about 750,000 miles in the orbital, and rather more than a million in the radial line.

On the outer side of one we feel the pulse at the wrist, the radial artery here lying close to the radius.

The position of the radial artery is described in Experiment 102.

THE FLEXOR PEDIS PERFORANS, OR THE DEEP FLEXOR OF THE PHALANGES.This muscle consists of three easily-divided portions: an ulnar, a humeral, and a radial, and has for points of origin the olecranon process of the ulna, the inner condyloid ridge of the humerus, and the posterior surface of the radius.

THE LARGE METACARPAL, OR COLLATERAL ARTERY OF THE CANNON.This, the larger terminal branch of the posterior radial artery, needs brief mention, for the reason that we shall be afterwards concerned with it in the operation of neurectomy.

The reflector and conical heater are sustained by a flat hub and eight radial spokes bent upward toward the ends at an angle of 45°.

At Huanchaca this stirrer has been made with four projecting radial arms, D D, Figs.

A railgrip, made to act at the curves as well as on the straight portions of the rail by being attached to a radial arm fixed to the under frame, assists the stability of the scaffold where required, but the gauge of the rails is altered to render the scaffold more or less stable according to its height.

The plane of failure, as visible on radial surfaces, is horizontal, and on the tangential surface it is diagonal.

This explains why on the radial surface of the test blocks the plane of rupture passes in a direction nearly following a medullary ray, whereas on the tangential surface the direction of the plane of rupture is obliquebut with an obliquity varying with the species and determined by the pitch of the spirals along which the medullary rays are distributed in the stem."

In the block at the left the surface of failure is radial; in the one at the right, tangential] |-| |

| | radial | tangential | |-++| | | Lbs.

Radial | Tangential | |

| | radial | tangential | |-++| | | Lbs.

The late wood of good oak, except for radial grayish patches of small pores, is dark colored and firm, and consists of thick-walled fibres which form one-half or more of the wood.

In typical heart shake the centre of the hole shows indications of becoming hollow and radial clefts of varying size extend outward from the pith, being widest inward.

When shake consists of several radial clefts it is termed star shake.

Shrinkage of the heartwood may be concentric as well as radial in its action, thus producing cup shake instead of, or in connection with, heart shake.

It frequently attacks the trunk as well, and boards cut from such trees are filled with long, radial holes which seriously damage or destroy the value of the timber affected. LOCALITY OF GROWTH

A considerable portion of every wood is made up of these rays, which for the most part have their cells lying in a radial direction instead of longitudinally.

Consequently the shrinkage along the rings (tangential) is fully twice as much as toward the centre (radial).

The coefficient of linear expansion of oak has been found to be .00000492; radial expansion, .0000544, or about eleven times the longitudinal.

Spruce expands less than oak, the ratio of radial to longitudinal expansion being about six to one.

Two penetrations each are made on the tangential and radial surfaces, and one on each end of every specimen tested.

The completed chain from the warping mill or the linking machine is now taken to the beaming frame, and after the threads, or rather the small groups of threads, in the pin lease have been disposed in a kind of coarse comb or reed, termed an veneer or radial, and arranged to occupy the desired width in the veneer, they are attached in some suitable way to the weaver's beam.