The president, secretary, auditor, or managing agent in this state of every telegraph or telephone company, whose line or any part thereof is located within this state, must annually, on or before March 1 of each year, make under oath to the Department of Revenue a return, in such reasonable detail as may be prescribed by such department, on all the property belonging to such company in this state and connected with the business, specifying the several counties in which such property is situated and the items of property situated in each of such counties, towns and school districts.