A gridiron slide valve has been used by Stephenson, which consists of a perforated square moving upon a face with an equal number of holes.

"I'm thankful enough if I can study day and night and keep myself up to 2.5," confessed Darrin, as he and Dan chatted over their gridiron longings.

Hepson was simply and heartily glad to find himself supported by two such promising gridiron men as Darrin and Dalzell.

Near it is a curious transit-clock, made by Graham, but greatly improved by Earnshaw, who so simplified the train as to exclude two or three wheels, and also added cross-braces to the gridiron-pendulum, by which an error of a second per day, arising from its sudden starts, was corrected.

"It was the first great gridiron battle I had ever seen, and so I was unprepared for the spectacle.

After another week "Pills" consented to Dave Darrin's going out for regular gridiron practice.

In their first year Dave and Dan had looked forward longingly to joining the gridiron squad.

The opposition team being an unusually good one that year, the Navy's gridiron pets were preparing to strain every nerve in the hope of victory.