If the Treasurer finds or reasonably believes that any person who is, or may be, liable for taxes upon personal property, the taxable situs of which was in the City on tax day, intends to depart from the City; or to remove therefrom personal property which is, or may be, liable for taxation; or to conceal himself or his property; or to do any other act tending to prejudice or to render, wholly or partly ineffectual the proceedings to collect such tax, unless proceedings therefor be brought without delay, he shall proceed to collect the same as a jeopardy assessment in the manner provided by law.