What is the current meaning of section 591 of the California Code of Civil Procedure on obstruction or interference with a telephone line?

On appeal, the defendant argued that section 591 applied "solely to obstruction or interference with a telephone line as distinguished from the telephone instrument itself. He point[ed] out that section 591, as it was initially enacted in 1872, was in turn based on an 1862 statute concerned with physical destruction of telegraph lines and appurtenances to such lines." (People v. Kreiling, supra, 259 Cal.App.2d at p. 704, fn. omitted.) The court responded: "The amendments to section 591 since the date of its original enactment have substantially changed the definition of the offense. The statute as it is presently written is not confined to telephone or telegraph lines. It encompasses conduct by which the transmission of telephone and telegraph messages is interrupted by any of the enunciated methods. One who tampers with a telephone instrument in such way as to preclude its use for receiving or placing calls 'obstructs . . . any line of . . . telephone . . . or apparatus connected therewith' as effectively as if he physically severed the telephone line." (Ibid.)