Opinion by

County commissioners may require as a condition of their consent to the use of a county bridge by a street railway, that the railway company shall bear the expense of strengthening the bridge, assume the cost of repairs and alterations that may be necessary in order to support safely the street railway and its traffic in addition to the ordinary public travel, and pay a reasonable rental. But when the proper local. and .municipal authorities have given their consent to the use by a street railway company of a highway of which a county bridge forms a part, the county commissioners cannot arbitrarily refuse the use of the bridge to the company. If they refuse their consent, and the bridge be of sufficient capacity to accommodate the general public travel and also the tracks and cars of the railway, the court, after ascertaining what will be necessary to strengthen the bridge for street railway traffic, may permit the company to enter upon the bridge and strengthen it, and when this has been done to the satisfaction of the court the company may be permitted to use the bridge for the purposes of its business upon giving security that the company will faithfully observe and abide by the terms and conditions relating to the manner of the use of the bridge, the repairs thereof, and the payment of the rent, which may have been or may thereafter be agreed upon by the parties, or, in the absence of an agreement may be determined upon by the court. These rules for the guidance of the court in such cases were laid down in the language, substantially, in which we have stated them in Berks *317Co. v. Reading City, etc., Cos., 167 Pa. 102, which, was followed and approved in Larue v. Oil City Ry. Co., 170 Pa. 249. In the cases cited the Supreme Court was dealing with the first occupation of a bridge by a street railway, but it is obvious that the rules enunciated apply equally well to a case where the company proposes to lay down an additional track and the original occupation of the bridge by a single track was without the express consent of the county commissioners. Instead of following these plain rules the court not only refused to enjoin the defendants from laying the additional track but also gave them permission affirmatively to go on with the work. Logically, it would seem clear that these questions, especially those relating to the safety and capacity of the bridge should be determined before the company is permitted to cross, and if the decree is to be construed as a postponement of the determination of these questions until final hearing it was erroneous. Unfortunately the court filed no opinion and the grounds of the decision are left to inference. It would seem, however, from the proofs, — although the pleadings show a somewhat broader issue — that the principal matter of dispute between the county commissioners and the defendants was the rental, and that so far as the safety of the bridge is concerned there is no such urgency as would require us to reinstate the temporary injunction, and compel the company to take up its tracks or cease to operate its railway pending the final determination of the case. We may remark, however, in order to prevent misunderstanding, that unless the parties agree in the mean time, or it is shown on final hearing to the satisfaction of the court that the bridge is of sufficient capacity and sufficient strength, there ought to be no hesitation in preventing the company from using it until it has been sufficiently strengthened or enlarged. But there is a manifest difference between the refusal of an interlocutory injunction restraining a railway company from laying an additional track and the granting of express permission to go on with the work. Under the special facts of this case the former may possibly be sustained upon the ground that there was no such immediate danger of irremediable injury as required interference by injunction before a full presentation, of all the facts of the case upon final hearing. The latter gives judicial sanction to an act which is unlawful unless *318the consent of the county commissioners is obtained, or the reasonable conditions upon which the right is to be exercised are ascertained and prescribed by the court and complied with by the railway company. This part of the decree is clearly erroneous.

Nor did the qualification that the work should be done under the supervision of the county commissioners cure the error. What work was referred to ? What supervision were they to have except, possibly, to see that the work was well done ? What authority had they under the decree to determine what was necessary to be done ? If they and the defendants could not agree upon that point who was to decide ? These questions sufficiently indicate the objections to the decree. It is vague and indefinite and not in accordance with the practice laid down in the case above cited. We think therefore that so far as it granted permission to go on with the work the decree should be reversed and the case allowed to stand as if the interlocutory injunction had been refused, simply. The court will then be at liberty on final hearing to make such decree concerning all the disputed matters as the proofs may warrant. In short, if the determination of the terms and conditions upon which the defendants were to use the bridge for the purposes of their business was to be postponed until final hearing, so ought the granting of express permission to have been postponed.

That part of the decree which grants permission to the defendants to proceed with the work complained of in the bill is reversed at the costs of the appellees, and the record is remitted with a procedendo.