Opinion by

The action in the court below was a joint one, instituted by father and son against the defendant for injuries to the son, a child of five years of age, caused by an accident alleged to be the result of the defendant’s negligence. The case was submitted without oral argument. This is usually undesirable but, because of it, we have given the more earnest heed to the testimony and the printed arguments of appellant and appellee. The case is well presented on both sides and we have little difficulty in reaching a conclusion. The defendant asked for binding instructions and the refusal to grant the request is the only error assigned.

The question of contributory negligence is not raised and the case turns exclusively upon the question of the negligence of the defendant. Was there evidence of such negligence to go to the jury? Was the speed of the car unusual and unreasonable ? Was the motorman alert and attentive to his duties ? Was the car under proper control? These were the questions as to which there was contradictory testimony. The speed at which motor cars are permitted to run within the city of McKeesport is eight miles per hour. The motorman knew this and .testifies that he was running at that rate. One of the witnesses for the plaintiffs, however, testified : “ I would say the car was running I suppose from 15 to 18 miles an hour.” This *640is very different from saying that the car was running “ unusually fast ” or “ quite lively ” or “ very rapidly ” or using any of the indefinite expressions which have been held to be insufficient to indicate the speed of a car. It is true that the witness qualifies his testimony by saying I suppose ” but all such testimony must necessarily be an opinion or an estimate, inasmuch as it is impossible for a bystander to measure accurately the speed at which a street car may be moving. The case is, therefore, not within the ruling in such cases as Yingst v. Lebanon, etc., St. Ry. Co., 167 Pa. 488, or Cominskéy v. Connellsville, etc., St. Ry. Co., 4 Pa. Superior Ct. 631. There is also other evidence in regard to the speed of the car which cannot be overlooked. It ran upon an up grade after the child was discovered a distance variously estimated at from 85 to 150 feet. This fact was of itself evidence that the speed was unusual or that the motorman was not attentive and alert in regard to the conditions which existed at the time the child appeared upon the track or that he had not such control of the machinery for applying the brakes and reversing the car as he should have had in a built-up portion of the city. The case is more nearly within Harkins v. Pitts, etc., Traction Co., 173 Pa. 146, 149, and, as to the evidence of the speed of the car, is, so far as the circumstances are concerned, somewhat similar to Gress v. Braddock, etc., St. Ry. Co., 14 Pa. Superior Ct. 87. We are clearly of the opinion that the court would not have been justified in taking the case from the jury.

Judgment affirmed.