In order to classify, regulate, and restrict the location of trades and industries, and the location of buildings designed for specified uses, to regulate and limit the height and bulk of buildings hereafter erected or altered, to regulate and limit the intensity of the use of lot areas and to regulate and determine the area of yards, courts, and other open spaces within and surrounding such buildings, the City of Evansdale is hereby divided into 11 classes of districts. The use, height, and area regulations are uniform in each class of district, and said districts shall be known as: