2053. The grand cause of the improvements which have been made in hothouses may be traced to their being no longer, as formerly, under the control of mansion architects. To civil architecture, as far as respects mechanical and chemical principles, or the laws of the strength and durability of materials, they are certainly subject, in common with every description of edifice; but, in respect to the principles of design or beauty, the foundation of which we consider, in works of utility at least, to be 'fitness for the end in view,' they are no more subject to the rules of civil architecture than is a ship or a fortress; for those forms and combinations of forms, and that composition of solids and openings which are very fitting and beautiful in a habitation for man or domestic animals, are by no means fitting, and consequently not beautiful, in a habitation for plants. Such, however, is the force of habit and professional bias, that it is not easy to convince architects of this truth; for structures for plants are considered by them no further beautiful than as displaying not only something of architectural forms, but even of opaque materials. Fitness for the end in view, we repeat, is the basis of all beauty in works of use, and, therefore, the taste of architects, so applied, may safely be pronounced as radically wrong. ï¿½ We shall consider the subject of hothouses as to the principles of construction, external forms, and interior details.