Improved Means for Marking the Lines of Lawn-tennis Courts and the like.

摘要

4485. Lean, C. March 22. Laying down lines for lawn-tennis courts and the like.-The lines of lawn-tennis courts &c. consist of T-irons d bolted to the bifurcated ends of pipes c which are cemented within clay or cement tubes b. The tops of the T-irons are flush with the layer f below the topmost gravel layer e, and the tubes b are embedded in the ground at a sufficient depth to avoid the detrimental influence of frost. The bolt-holes in the T-irons are elongated to permit of expansion and contraction due to the influence of heat.