In the case of towns and cities a further division of the land is required for the purpose of conveyance and description. This is secured by means of plats and subdivisions. Under this system the owner of, say, the northeast quarter of section 16 in a certain township will have a map made of such quarter section platted off into blocks and lots. This map will be placed on record and a lot in such subdivision can be transferred by a description similar to the following: Lot 13, block 7, in William Smith's Subdivision of the northeast quarter section 17, township 13 south, range 8 east of the third principal meridian.