In all cases where any person or persons shall perform any of the work mentioned in the preceding sections, either under contract with the city or by virtue of permission obtained by authority of the city, such person shall be answerable for any and every damage which may be occasioned to persons, animals or property by reason of carelessness in any manner connected with said work. (R.O. 1959, Ch. 36, Art. 6, Sec. 10)