From the interior point of view, the main lobby is the most important single feature in the building. It should be very spa cious, since both tenants and visitors pass through it or congregate there, but, as has been pointed out, it should be so designed as always to appear busy and full of life. It is generally two storeys high with surrounding galleries. It is sometimes placed below a light well in the centre of the building so as to give some degree of natural light during the day, but in tall buildings skylights have little value and artificial "daylight lamps" are used above them to give daylight effect. Because of their large size the public rooms have to be formally treated, but their architectural formality is often successfully relieved by the use of screens of growing plants and the informal arrangement of the usually luxurious furniture.
The hotel is following in the way of other forms of business aad is tending to concentrate in larger and larger units. In Europe, however, the height limit placed on buildings has prevented the adoption of the modern efficiency methods of hotel management with the result that it is impossible for enough typical floors to be superimposed for economic operation.
Apartment-hotels have developed on a large scale from the modern demand for expert service in living conveniences that has tended to make hotels more and more popular as places of perma nent residence. They differ from the apartment house in that the suites have no kitchens and the building generally contains one or more common dining-rooms. They differ from the hotel in that the rooms are not standardized and may or may not be furnished and they are designed without commercial spaces and many of the social rooms found in large hotels. Often tenants contract for their space on long term leases, furnishing and decorating to suit themselves. Sometimes dining-rooms are pro vided in the apartments, and then meals are served from the hotel kitchen. The management provides service at an hourly rate, thereby eliminating all domestic cares for the tenants. This type of apartment is prevalent in the United States, for there the idea of communal services is becoming increasingly popular.
The best source of information on modern apartment and hotel architecture is the various architectural publications, for which see bibliography under ARCHITECTURE. (H. W. C.)