It shall be unlawful for any person, firm or corporation who obtains a permit under the pro visions of this article to do any excavation of any kind which may create or cause a dangerous condition in or near any street, alley, sidewalk or public place of the town without placing and maintaining proper guard rails and signal lights or other warnings at, in or around the same, sufficient to warn the public of the excavation or work, and to protect all persons using reasonable care from injuries on account of same.
('76 Code, § 4-1025) Penalty, see § 95.99