The ultimate concrete question now in this case is whether a telephone company using a low tension current of electricity and using the earth as a return circuit, the earlier occupant of a highway, or an electric power and light company, the 'later occupant, using a high tension current, shall bear the expense of installing a metallic return circuit in the telephone lines in order to eliminate the electromagnetic induction of the telephone lines by the power lines.
[1-3] Without going extensively into the scientific aspects of the case, it may be stated that the evidence shows that electric interference between these lines arises in two ways; by conduction and bjr induction. Induction is of two kinds; static and magnetic. Interference by conduction ma}^ be practical^ eliminated by the proper erection and maintenance of the power line. Interference by static induction may be overcome by a proper balancing of the electric current in the power line. We take it that there is no dispute in this case, but that the power company must eliminate interference by conduction and by static induction. If there is a dispute we nevertheless hold that it mu(st do so. Electromagnetic induction is the transmission of electricity from, one electric circuit to another by means of an electric field. See Curtis, Electricity, § 349. This kind of interference may be practically prevented by a co-ordinated transposition of the wires on both systems, but this may be accomplished only where the electric circuits on both systems are metallic; hence the remedy cannot be applied to an earth return telephone line. No other practical method of prevention of magnetic induction is' suggested in the evidence.
Plaintiff owns and operates certain telephone lines in South Dakota," both rural and toll linep, and in particular owns and operates rural lines on the highway between Ashton and Frankfort.
Defendant owned and operated an electric light and power *453plant at Ashton, with lines to neighboring communities. In September, 1916, pursuant to permission of the county board, it set a line of poles between Ashton and Frankfort, and was about to install the necessary wires for the purpose of transmitting a current of about 6,600 volts, under what is called a 3-wire 60-cycle alternating" high power system:. Plaintiff sought injunction as an interference with its lines. The case was presented on its merits upon the application for a temporary' injunction, and in February, 1917, the trial court vacated the restraining order on condition that defendant should make certain changes in the construction of its line, take certain precautions to prevent interference by conduction, and move a portion of plaintiff’s line to the other side of the highway. Defendant then completed its line, and 'began the transmission of its high power current. In November, 1917, a' further hearing was had. Plaintiff submitted proof to show that further requirements were necessary to protect plaintiff’s lines. Defendant submitted proof that it had complied with the order of February, 1917. In August, 1918, the trial court filed its findings of fact and conclusions of law, and entered judgment denying" the injunction. Thereupon and from an order denying a new trial plaintiff appeals.
Appellant’s right to the use of the highway arose from section 554,. Rev. C. C. 1903 (section 9791, Rev. Code 1919), and it had been in the actual operation of its rural line on said highway since about the year 1910.
[4] Respondent’s right to the use of the highway arose from chapter 369, Laws 1913 (Rev. Code 1919, §§ 8591-8594), but said chapter contains the following proviso:
“Provided that such transmission line shall not interfere with the service of any telephone or telegraph lines already constructed on such highway.”
Notwithstanding the fact that the lines of the respective parties are on opposite sides of tire’ highway, it appear^ by the clear preponderance of the evidence that by reason of electromagnetic induction the service of appellant’s lines is, and will ■continue to be, substantially interfered with.
[5] Appellant rather faintly contends that the Legislature was without pow'er to authorize the occupancy of the rural high*454ways for light and power transmission lines other than for the purpose of lighting the highways. We have no' hesitancy in holding that when land is taken or dedicated for use as a highway, such taking or dedication should be presumed to be, not merely for such purposes and usages as were' known and in vogue at the time oí such taking or dedication, but also for all public purposes present and prospective, then known or unknown, consistent withl the character of such highways and not actually detrimental to the abutting real estate. Cater v. N. W. Tel. Exch. Co., 60 Minn. 539, 63, N. W. in, 28 L. R. A. 310, 51 Am. St. Rep. 543; People v. Eaton, 100 Mich. 208, 59 N. W. 145, 24 L. R. A. 721; Com. v. Morrison, 197 Mass. 199, 83 N. E. 415, 14 L. R. A. (N. S.) 194, 125 Am. St. Rep. 338; Mordhurst v. Ft. Wayne & S. W. Tr. Co., 163 Ind. 268, 71 N. E. 642, 66 L. R. A. 105, 106 Am. St. Rep. 222, 2 Ann Cas. 967; Brandt v. Spokane & Inland Empire R. Co., 78 Wash. 214, 138 Pac. 871, 52 L. R. A. (N. S.) 760. Indeed it was the recognition of this principle that determined the decision of this court in Kirby v. Citizens’ Tel. Co., 17 S. D. 362, 97 N. W. 3, 2 Ann. Cas. 152.
Appellant contends that under the rule that priority in time carries w|ith it priority of right, recognized by this court, in view of the proviso above quoted in Tri-County Mut. Tel. Co. v. Bridgewater Elec. Power Co., 40 S. D. 410, 167 N. W. 501, its right to the use of the earth as a return circuit should be protected.
[16] Respondent contends, and our colleague agrees therewith, that under tire rule “Sic utere tuo,” etc. (Rev. Code 1919, §45), tire appellant must suffer the interference with its service caused! by electromagnetic induction, or must abandon the use of the earth as a return circuit, and at its own expense install a metallic return circuit on the lines interfered with, as substantially found by the trial court. If the Legislature had so declared, we believe no constitutional principle would have been violated. If there had been no legislative direction either way, we believe that under the excellent argument and authorities advanced this court, with perfect propriety, might have laid down that rule. Curtis, Electricity, §§ 356, 357; Cumberland T. & T. Co. v. United Electric Ry. Co., 93 Tenn. 492, 29 S. W. 104, 27 L. R. A. 236; Cumberland T. & T. Co. v. United Ry. Co. *455(C. C.), 42 Fed. 273, 12 L. R. A. 544; Lake Shore & M. S. Ry. Co. v. Chicago, L. S. & S. Ry. Co., 48 Ind. App. 584, 92 N. E. 989, 95 N. E. 596; Cincinnati Inclined Ry. Co. v. City & Suburban Tel. Ass’n, 48 Ohio St. 390, 27 N. E. 890, 12 L. R. A. 534, 29 Am. St. Rep. 559; note Ann. Cas. 1916A, 135; Panton v. Holland, 17 Johns. (N. Y.) 92, 8 Am. Dec. 369.
But the Regislature did declare that the later transmission line should not “interfere with the service of any telephone or telegraph line already constructed on such highways.”
[7] We must presume that the Regislature of 1913 knew; of the extensive occupancy of the highways of 'the state by rural telephone lines using the earth as a return circuit. It is said there were then 20,000 miles of such lines in this state. It is a fact in this case that no power and light transmission line couldl be installed between Ashton and Frankfort without occupying a highway already occupied by such lines. We think the manifest intention of the Regislature was to protect telegraph and telephone lines previously constructed from interference with their service. Any other interpretation would merely give protection to such lines from the negligence of the power and light company, a protection which they .would have without that statute. 'Curtis, Electricity, § 357. If respondent is right in its view, protection is merely afforded (in the absence of negligence) to those lines that need no protection. But on the other hand, we do not 'believe that it was the intention of the Regislature to exclude the power and light transmission lines from occupied highways, provided a remedy could be found by changes and improvements in either system. If appellant must bear the expense of changing its system to a metallic return circuit, clearly it has not been protected in the right given it by that statute. If, however, such expense is borne by the power and light company, then the telephone company cannot justly say that it is not protected in the right acquired by reason of earlier occupancy of the highway. The respondent, therefore, should bear such expense.
[8] Of course, in holding that the Regislature by the proviso intended to protect previously constructed! telephone and telegraph 'lines using the earth as a return circuit, it necessarily follows that under such' plan there must be proper construction *456and -proper maintenance. If there be faulty -construction or faulty maintenance such defects, must be remedied at the expense of the low power lines. The Legislature did not intend to encourage negligence.
The case of Lake Shore & M. S. Ry. Co. v. Chicago, L. S. & S. Ry. Co., supra, is cited by respondent as analogous in facts and as stating the law which should be applied in this case. In that case the court discussing priority of right in the occupancy of public highways said:
“But this fact [priority of occupancy] can have no legal bearing upon the question involved, for, as said in Thompson, Electricity, ' p. 57, ‘In both of these cases the one having the prior right must yield his right and submit to damage and inconvenience to some extent for the good of his neighbor and of society.”
[9] This statement contains the gist of respondent’s entire contention in thi,s case, and we might be disposed to adopt the view thus expressed had the legislature of this state not declared and' established a -different rule which this court in the exercise of its exclusively judicial powler cannot change or ignore. The Legislature in direct and specific terms has declared that the later transmission lines should “not interefere with the service of .any telephone or telegraph line airead} constructed- on such highway.” We are told ’ that the enforcement of this rule necessarily bars the later transmission lines from using the public -highways, and thus denies them a right intended to be conferred by- the Legislature. This assumption is not true. The right of 'both parties to occupancy of the -highways must be assumed, and such construction placed upon the statute as will enable both to use such highways. This we do by placing on the later transmission line the burden of removing interference by every scientific means, and! by holding that telephone and telegraph lines must allow such changes to be made in their lines at the expense of the transmission line as are necessary to remove interference resulting from the construction and use of such transmission line. The power of -the court to so frame its injunctional order as to accomplish .this purpose can hardly be questioned, and this we have done.
[10] At the time of beginning this action appellant upon *457the showing made was entitled to an injunction. Tri-County Mut. Tel. Co. v. Bridgewater Electric Power. Co., supra; Curtis, Electricity, § 365. Since it w'as denied and the question now is one of dollars, it does not' follow that the appellant should be remitted to his remedy in an action at law. A court of equity having taken hold of the case is authorized to determine even the question of dollars.
The judgment and order appealed from are reversed, and the cause is remanded for further proceedings in harmony with this opinion. It is suggested that injunction may not necessarily be the immediate remedy. It is hoped that the parties may agree upon the sum that respondent should pay appellant as the necessary expense of installing so much of a metallic return circuit upon its lines as will obviate electromagnetic interference. If they do not agree, then evidence should be taken and the matter determined by the trial court. If the respondent unreasonably delays compliance with the court’s requirements, injunction may then be resorted to.