If sacrifices are necessary in picking out material for the planned campaign, the head coach is more likely to sacrifice speed in the forward line than in the backfield, for the backs have an enormous amount of ground to cover against the improved running game, the unrestricted forward pass - unrestricted beyond the line of scrimmage - and the quick kicking under the line that was restored to football after some experimenting with a five-yard restriction back of the line. The restriction was taken off the kicking in the interest of strengthening the attack, greatly increasing both the actual kick and the threat thereof. In the case of a light back who is built close to the ground the rule regarding weight may be overlooked now and then, for 150 pounds with a low center of gravity is sometimes as good as 180 pounds well up in the air. These short, stocky backs, however, are extremely rare. On the defense as well as on the attack weight is of the greatest value, for under the rules as they are worked out to-day individuals in the defense come in for some hard hammering at the hands of fast and heavy interference, that, unless the forwards be alert to the last degree, has been able to get up considerable momentum.

Ler us consider for a moment the attack so far as its individual members are affected by the latest rules. Under the old rules it was possible to make a first down in three tries when the backs averaged 3 1/3 yards on each attempt. But since kicking was usually resorted to on the fourth down or third try, the backs were really required to average 5 yards each to earn a first down save when inside the ten-yard line, when the average naturally and automatically returned to 3j yards. Under the revised code the backs have been compelled to average 2} yards in order to earn a first down, but since the fifth down, or fourth try has been given over to punting, this has meant that the average has been after all, 3 1/3 yards, with the advantage over the old code that the three tries could be used without losing the ball.

Naturally the decreased necessary average means a premium on heavy backs, for the runner's length is of more importance even than it used to be. Therefore the man who is fairly sure of his own length every time, and is big and strong enough to keep his feet when tackled, must always be in great demand even though unable perhaps to make a ten-yard gain at any time in the course of the game.

A Clean Head-On Tackle

The tackier has hit hit man so hard that the latter has had to use both hands to cling to the ball. Furthermore, he is falling in such a way that he will not be able to add his own length to the run.

Now the back of to-day must depend upon his own efforts to make ground after he is tackled, since his team mates cannot assist him, and the big, rugged back is more likely to keep fighting along than the small one, no matter how speedy the latter may be. Under the ten-yard, three-down rule, every effort was made to get a fast man loose, but under subsequent rules there has been a consistent effort to turn out backfields able to add the runner's length to small, but consistent gains. Considering that the ball is not held head high, the back of reasonable stature should be able to add very nearly a yard to his run if he is big and strong enough to trouble the individual tackier, and this means, of course, that the average necessary for a first down may be markedly reduced simply by picking the right type of back.

The big man, if he is quick enough to make the sharp turn so valuable when carrying the ball, can meet his tackier head on, and so carry on, over him, whereas the lighter man is of necessity stopped the moment he strikes the secondary defense; and if he depends upon wide end skirting is apt to be thrown for a loss. Even a small team, therefore, should have at least one big, rugged man in the backfield, even at the cost of removing him from the line. Men of the Wendell or Heston type are the darlings of the coaches.

The next problem in selecting material will be its value in the interference. Here, too, the big man is in demand, for even if slightly lacking in speed, be will be able to make up for it in the power of his lunge into the tackier. In the quick dashes just over or inside tackle or guard, it is not the number of men preceding the runner, but their power when they strike, that makes or mars the play. Their work will be highly individual, as indeed, has been most of the effective interference of recent years.

It would be well for the head coach to decide, when picking out his men, whether he intends using a guard in the interference, for this will make a difference in his selections. The value of a guard so used - when the interference is not made individually beyond the line of scrimmage - is problematical. Some of the best coaches in the country believe in swinging the guard around, while others, equally capable, maintain that it is suicidal. The interfere!', whether a line man or a back, faces the necessity of accounting for one opponent without assistance, and if necessary, going to earth with him, leaving his back to fight on alone. Here is where weight and strength count and count heavily.

Just how important a factor was the heavy back in the remarkable season of 1912 may be gained from a study of the Harvard-Yale game that year, when Wendell and Hardwick of Harvard at times put out of the play men on the defense who hitherto had used up two interferers. Percy Haughton, the head coach, was able to build up an extremely advanced and effective attack, since he had backs who often could do the work in interference allotted in former years to a tackle and end, or a pair of backs. This was a tremendous advantage and a great factor in Harvard's success against Princeton and Yale.

In the course of progress toward a touchdown the backs that are worked into the interference are expected to put out of the play not only the backs of the secondary defense, but line men who may be left uncovered in the course of the run, and these line men are often uncovered nowadays, since the old method of boxing the defensive tackle with the tackle and end is no longer in such high favor. The tackle in the modern game is often called upon to put the defensive end out of the play, while an interfering back and the attacking end take care of the line man, generally the tackle, and occasionally the guard or "roving" center. It often happens that the back is expected to handle the defensive tackle alone, which is something of an undertaking for any but a big and rugged player.