The tackles and guards should go through on as small an arc of the circle as possible in order not to pull the line open. The centre should hold his ground until he sees that his position is not attacked, and then take the nearest hole to the runner. The rush-line half should stand just outside of the tackle. The half should go through between end and tackle, as a rule following close upon the end. The ground between end and tackle is the most dangerous. The half should be in a position to help both end and tackle. If the runner turns inside of end the half-back should be there to pick him up if he goes outside.
The quarter-back should hover around behind the centre rush and help him in looking after the centre holes, at the same time keeping a sharp lookout upon the guard and tackle holes. He should play more of a safety game. At the same time, if he sees a good opportunity to go through he should do so. The quarter, however, should never undertake to play between guard and centre. How much of a free lance the quarter may be will depend largely upon the strength of the centre. The full-back stands the usual distance back, and should advance toward the rush-line with every play. The position of the players after getting through should be something like the dotted rings in Fig. 3. To secure this position, the men in the forward-line must break through sharply and cleanly, not occasionally, but every time.
When the opposing side is going to kick from some point between the two 35-yard lines, it is a good rule to have the ends drop back and out about five yards. That enables them, in case of a false kick, to get back to stop an end run, or, in case it is a _bona fide_ kick, to get back so as to protect the backs while catching the ball. When the opposing team kicks inside its own 35-yard line, the ends should break through with the other forwards to help stop the kick.
The University of Pennsylvania has a unique and singular style of defence used by no other eleven, so far as the writer knows. Its point of difference from that of other teams lies in the play of the tackle and the rush-line half-back. When the ball starts, the half-back takes the tackle and literally hurls him through the line on the inside of his man, while the half and the end take the outside. This scheme seems to work pretty well, the tackle almost invariably gets through, and if the play has not advanced beyond centre, he is in a good position to stop it. The hole between the guard and tackle being well protected by the tackle going through it every time, the guards face in toward the centre, and so protect the centre holes fairly well. The line from tackle to tackle is very strong in this defence.