"It is not necessary to set forth the provisions of the Ohio Constitution which are thought to be infringed. The question is the same under both Constitutions, namely, as stated by appellee: Is the ordinance invalid, in that it violates the constitutional protection 'to the right of property in the appellee by attempted regulations under the guise of the police power, which are unreasonable and confiscatory'?

"Building zone laws are of modern origin. They began in this country about 25 years ago. Until recent years, urban life was comparatively simple; but, with the great increase and concentration of population, problems have developed, and constantly are developing, which require, and will continue to require, additional restrictions in respect of the use and occupation of private lands in urban communities. Regulations, the wisdom, necessity, and validity of which, as applied to existing conditions, are so apparent that they are now uniformly sustained, a century ago, or even half a century ago, probably would have been rejected as arbitrary and oppressive. Such regulations are sustained, under the complex conditions of our day, for reasons analogous to those which justify traffic regulations, which, before the advent of automobiles and rapid transit street railways, would have been condemned as fatally arbitrary and unreasonable. And in this there is no inconsistency, for, while the meaning of constitutional guaranties never varies, the scope of their application must expand or contract to meet the new and different conditions which are constantly coming within the field of their operation. In a changing world it is impossible that it should be otherwise. But although a degree of elasticity is thus imparted, not to the meaning, but to the application of constitutional principles, statutes and ordinances, which, after giving due weight to the new conditions, are found clearly not to conform to the Constitution, of course, must fall.

"The ordinance now under review, and all similar laws and regulations, must find their justification in some aspect of the police power, asserted for the public welfare. The line which in this field separates the legitimate from the illegitimate assumption of power is not capable of precise delimitation. It varies with circumstances and conditions. A regulatory zoning ordinance, which would be clearly valid as applied to the great cities, might be clearly invalid as applied to rural communities. In solving doubts, the maxim 'sic utere tuo ut alienum non laedas,' which lies at the foundation of so much of the common law of nuisances, ordinarily will furnish a fairly helpful clue. And the law of nuisances, likewise, may be consulted, not for the purpose of controlling, but for the helpful aid of its analogies in the process of ascertaining the scope of, the power."...

"The decisions enumerated in the first group cited above agree that the exclusion of buildings devoted to business, trade, etc., from residential districts, bears a rational relation to the health and safety of the community. Some of the grounds for this conclusion are promotion of the health and security from injury of children and others by separating dwelling houses from territory devoted to trade and industry; suppression and prevention of disorder; facilitating the extinguishment of fires, and the enforcement of street traffic regulations and other general welfare ordinances; aiding the health and safety of the community, by excluding from residential areas the confusion and danger of fire, contagion, and disorder, which in greater or less degree attach to the location of stores, shops, and factories. Another ground is that the construction and repair of streets may be rendered easier and less expensive, by confining the greater part of the heavy traffic to the streets where business is carried on. The Supreme Court of Illinois, in City of Aurora v. Burns, supra, pages 93-95 (149 N. E. 788), in sustaining a comprehensive building zone ordinance dividing the city into eight districts, including exclusive residential districts for one and two family dwellings, churches, educational institutions, and schools, said:

'The constantly increasing density of our urban populations, the multiplying forms of industry and the growing complexity of our civilization make it necessary for the state, either directly or through some public agency by its sanction, to limit individual activities to a greater extent than formerly. With the growth and development of the state the police power necessarily develops, within reasonable bounds, to meet the changing conditions. ..

'... The harmless may sometimes be brought within the regulation or prohibition in order to abate or destroy the harmful. The segregation of industries, commercial pursuits, and dwellings to particular districts in a city, when exercised reasonably, may bear a rational relation to the health, morals, safety, and general welfare of the community. The establishment of such districts or zones may, among other things, prevent congestion of population, secure quiet residence districts, expedite local transportation, and facilitate the suppression of disorder, the extinguishment of fires, and the enforcement of traffic and sanitary regulations. The danger of fire and the of contagion are often lessened by the exclusion of stores and factories from areas devoted to residences, and, in consequence, the safety and health of the community may be promoted. ...

'... The exclusion of places of business from residential districts is not a declaration that such places are nuisances or that they are to be suppressed as such, but it is a part of the general plan by which the city's territory is allotted to different uses, in order to prevent, or at least to reduce, the congestion, disorder, and dangers which often inhere in unregulated municipal development.'