The mayor and city council of a city of the first class may levy a tax, not exceeding seven cents on each one hundred dollars upon the taxable value of all the taxable property in such city, for the purpose of paying the cost of lighting the streets, lanes, alleys, and other public places or property of the city, for the purpose of furnishing water, heat, or power for the city, or for the purpose of buying, establishing, extending, or maintaining such waterworks, gas, electric, or other light works, or heating or power plant, not exceeding three and five-tenths cents on each one hundred dollars upon the taxable value of all the taxable property in such city for any one of the respective purposes.