Opinion by
Mr. Justice Frazer,Plaintiff owned and operated a weaving mill located in the Borough of Milton, and defendant furnished electric current for lighting plaintiff’s property. On January 21,1913, plaintiff’s mill and contents were destroyed by fire, caused by a short circuit at the point where defendant’s service wires passed through the outer wall of plaintiff’s building to connect with a switch box and fuse box located inside the mill. Plaintiff’s evidence tended to show that at the time of the fire the wires were attached to the building by glass insulators mounted on wooden brackets and entered the building through iron conduits, which were not fitted with porcelain tubing and one of which was without bushing at one end, to prevent the insulation on the wire from rubbing against the sharp edge of the pipe through which it passed. The conduits sloped inward instead of outward and the wires at the point where they entered the mill were without “drip loops” to prevent water from rain and snow entering the conduit and flowing into the building. As a result of such defective construction water entered the tubes or conduits, which contained wires with insulation not fitted to withstand moisture. This condition or the absence of proper insulation around the wires as they entered the conduit or the combination of both, caused a short circuit to be created, which set fire to the building and resulted in its destruction. In attempting to establish defendant’s liability by showing that it put in place the defective wiring, plaintiff called its bookkeeper as its only witness on this point; the trial judge considered the testimony of this witness so indefinite and unreliable that he refused to permit the jury to pass upon it, and sustained defendant’s motion for binding instructions. The ease thus turned upon the question whether plaintiff or defendant was responsible for *82the wiring which entered the building. A brief examination of the evidence will show the trial judge committed no error in thus ruling.
That the work of wiring the building on the inside was done by an electrician employed by plaintiff is undisputed. This workman was called as a witness on behalf of defendant and testified to inserting the conduits and wires through the wall of the building from the inside to the outside and making them ready to be connected by the electric company. He further said the conduits: were placed through the wall with a downward slant toward the outside and were lined with porcelain insulators. A witness in the employ of the predecessor in title of defendant, called by defendant, testified to connecting the company’s service main lines with the ends of the wires which extended through the wall to the outside of the building but did no work in connection with the wiring on the inside. This testimony was corroborated by another witness who assisted plaintiff’s electrician in wiring the building. The only contradictory evidence was the testimony of the bookkeeper of plaintiff who stated the wires were not extended through the wall by plaintiff’s electrician but that this work was done by employees of the electric light company when connection was made with the service wires from the outside. This witness did not testify positively to facts within his knowledge but rather to conclusions based on his recollection that no charge was made for placing the conduit and wires through the wall of the mill in the bill for materials, which came through his hands as bookkeeper. His entire testimony on this point is vague and indefinite as well as contradictory. In his direct examination the witness said he saw employees of the electric company place in position the conduits and wires which extend through the wall but on cross-examination repeatedly said he was testifying to the best of his knowledge only and avoided making positive statements. After considerable evasion of the direct question whether he actually saw *83any person do this particular part of the work, he answered in the affirmative. On being further pressed, however, it appeared he merely saw the electric company’s employees at work and concluded the connection inside of the building was made by them as he noticed no special charge for that work on the bill of their own contractor. The bill referred to by this witness was produced later and the item of charge for this work pointed out; he then admitted he saw no one actually do the work and that the electric light company’s men worked entirely on the outside of the building. Such testimony is without force when opposed to the clear and positive statements of the men who actually did the work and the trial judge was right in refusing to permit the jury to pass upon it: Hyatt v. Johnston, 91 Pa. 196; Howard Express Company v. Wile, 64 Pa. 201.
It was argued on behalf of plaintiff, however, that even if the wires were constructed by plaintiff’s workmen, defendant still owed the duty of inspection because the defect, which lay between the outside service wire and the meter which was under the direct control of defendant, although inside plaintiff’s building, was readily discoverable by proper inspection.
Although there is conflict of authority on the question of extent of duty of electric companies in regard to the safety of appliances owned and maintained by its customers, the weight of authority in other jurisdictions supports the view that the company is not bound to inspect such appliances and is not generally liable for injuries or damages caused by reason of defect therein: 7 Thompson on Negligence, White’s Supplement, Section 807; 1 Joyce Elec. Law, 2 Ed., Section 445; Curtis on Electricity, pages 417 and 492 and cases cited. The exact question appears to be without precedent in Pennsylvania. It is generally held, however, that a person or company furnishing electricity is bound to know not only the extent of the danger incident to its use but to exercise the highest degree of care practicable to avoid *84injury to persons coining in contact with its appliances and to make the wires safe, not only by proper insulation but to keep them so by constant oversight and repair: Fitzgerald v. Edison Electric Illuminating Co., 200 Pa. 540; Herron v. Pittsburgh, 204 Pa. 509; Yeager v. Edison Electric Co., 242 Pa. 101. These cases, however, do not decide the question involved here. To sustain its right to recover, Fedorawicz v. Citizens Electric Illuminating Co., 246 Pa. 141, is relied upon by plaintiff. In that case a child was injured by coming in contact with a charged broken electric light wire lying in the public highway. The defense was that the line was constructed at the expense of a lumber company for its own use, which company agreed to maintain, repair and provide for its inspection. This court, by Mr. Justice Stewart, said at page 146, in quoting from the case of Daltry v. Media Electric Light, Heat & Power Company, 208 Pa. 403: “That the company did not construct the line at its own expense cannot relieve it from the duty to exercise care in keeping it in proper condition and repair during the period the wire carried its electric current. The ownership of the wire cannot affect the company’s liability for failure to observe this duty under the facts disclosed by the evidence in this case. When charged with electricity the wire was in the possession and control of defendant company, so far as concerned its duty-to keep it in repair and in proper condition and position to protect those who might come in contact with it. The danger lay not in the wire but in the subtle fluid sent through it by the defendant company. It was not the wire that injured the boy but the electric current which it bore from defendant’s dynamo. The use of the wire by the defendant and not the wire itself, caused the injury to the child, hence it logically follows that notwithstanding the ownership of the wire may have been in another, the defendant company must be considered as in possession of and as using it at the time of the accident and therefore responsible for any injury resulting *85from the failure to inspect and keep it in proper condition and repair Avhen charged Avith the company’s electricity.” The case of Daltry v. Media Electric Light, Heat & Power Co., 208 Pa. 403, quoted from by the court in the above case, was an action for damages for injury to a child by coming in contact with the end of a broken electric light wire which when in place extended across a lawn and connected defendant’s pole with the house. This wire was installed at the tenant’s expense and the premises were vacated when defendant discontinued the service by taking out the fuses in the transformer located under the eaves of the house. The current was still permitted to run through the service wire, which subsequently broke and hung down at the point where the child came in contact with it. This court by Mr. Justice Mestrezat, said after using the language quoted above, “The ownership of the wire is not controlling as the liability for an injury caused by coming in contact with it is determined by the principle announced in that class of cases in which it is held that an electric railway company or an electric light company is responsible for injury where it negligently permits its wire to come in contact with another company’s telephone or telegraph Avire, which transmits the current and thereby causes an accident.” Zinkiewicz v. Citizens Electric & Illuminating Co., 53 Pa. Superior Ct. 572, was also a case of injury to a pedestrian by coming in contact Avith a broken electric wire lying along the highway. It was there held to be no defense that defendant had received pay from the consumer for putting the wire in place and the consumer had agreed to notify defendant of defects in the appliances which might arise. It will be noted the above were all cases of injuries to third persons and are in this respect distinguishable from the case before us. Here the question arises between the company and the consumer, the very person who erected, owned and controlled the defective wire, and towards Avhom no duty on the part of defendant has been shown to exist in so *86far as inspection of the consumer’s appliances is concerned.
Plaintiff offered evidence of custom regarding the construction of service wires which offer was rejected by the trial judge. It is contended in the 16th assignment of error plaintiff was thus prevented from fixing liability on defendant. The offer was to ask the witness “Whether it was the general custom and practice of electric light companies to make the connection and run the service wires from the line or main cable wires to the building through the wall and into the fuse box, cut out box, as some evidence to go to the jury from which they may determine under whose supervision this outside construction was.” The trial judge properly sustained an objection to this offer. The question was not what was the custom as to installing wires, but who installed the particular wires in this case. On this point there is direct and positive evidence without substantial contradiction, and proof of a custom contrary to the actual fact of the transaction would have been of no avail: Brown v. Pennsylvania Casualty Co., 207 Pa. 609. To admit proof of custom under such circumstances would take from the parties the right to regulate their business dealings and relations as they might see fit and would in effect limit their right to contract. This cannot be done: Stoddard v. Emery, 128 Pa. 436; Harris v. Sharpless, 202 Pa. 243.
The testimony of the electrician who did the wiring through the wall and also that of his assistant was to the effect that the work was properly done and since a contrary condition appeared at the time of the fire, plaintiff contends the burden is on defendant to show it was not at fault. This contention cannot be sustained as one who charges negligence must prove it. While there are exceptions to this rule in which the doctrine of res ipsa loquitur applies the facts of this case do not bring it within the exception. In East End Oil Co. v. Penna. Torpedo Co., 190 Pa. 350, it was said at page 353, “The *87maxim res ipsa loquitur is itself the expression of an exception to the general rule that negligence is not to be inferred but to be affirmatively proved. The ordinary application of the maxim is limited to cases of absolute duty or an obligation practically amounting to that of an insurer. Cases not coming under one or both of these heads must be those in which the circumstances are free from dispute and show not only that they were under the exclusive control of the defendant but that in the ordinary course of experience no such result follows as that complained of.” It is not contended that defendant comes under either of the enumerated heacls. As to the last mentioned condition it is sufficient to say that in the present case the circumstances are not free from dispute and the wires and attachment which caused the loss were not under the exclusive control of defendant. The cause of the accident was a defectively insulated wire or defectively constructed apparatus for conveying the wire which was fully explained by plaintiff’s own witnesses. Under these circumstances there is not room for presumption and inferences and the rule of res ipsa loquitur does not apply.
The judgment is affirmed.