East and west numbers shall begin on the east boundary of the Village and north and south house numbers shall begin on the north boundary of the Village, and such numbers shall be a continuation of the numbering currently prevailing in the City of Chicago, being an extension thereof. Because of the variation in lot sizes, one number shall be assigned by the Building Commissioner to each fifty feet of frontage, which number of each successive fifty feet shall be increased by two. In the case of irregular or curving streets, the Commissioner shall assign numbers to each fifty feet of frontage on a street, such assignments to be made as nearly as possible in accordance with this section.