The trial court’s instruction allowing plaintiff to recover lost earnings while unable to operate his tractor-trailer, which before his injury he drove himself, is supported by testimony that he had in the past hired a substitute driver for $160 per week although he had not hired a substitute during the period for which lost earnings were claimed because he couldn’t hire anyone he would trust with his rig. See Murphy v. Pittsburgh Rys. Co., 292 Pa. 191, 140 A. 897 (1927); Annotation, 122 A.L.R. 297, 320.

Affirmed.