"It is plain common sense that the ideal greenhouse is one in which the light is most nearly that which exists outside, and in which the heat is as evenly distributed. It is practical experience that a structure with as few angles and turns m it as possible and with a minimum of woodwork in its superstructure, best answers these conditions.... Greenhouse building has developed into a special industry, and the modern American greenhouse is the highest type of construction. It is built with as careful calculation to its situation and its requirements as is the country dwellinghouse. Such a thing naturally is not cheap." "The low-priced 'cheap greenhouse' is a makeshift of some sort. Perhaps its roof is constructed of hotbed sash, a perfectly feasible method of construction, which for ordinary, commonplace gardening will answer admirably. Or, its foundation is merely the plain earth. Such a building does admirably in the summer time, and even in the late spring and early autumn; but woe betide the enthusiastic amateur in winter, who, being possessed of one of these light greenhouse structures, has indulged in a few costly, exotic plants. They will be frozen, to a certainty! It is economy to pay a fair price in the beginning to secure a properly built greenhouse that will withstand the trials of winter." "If iron frame is used instead of wood there is greater durability, and the structure being more slender, will admit more light, but the cost will be increased." "It makes very little difference in cost what shape of house is to be erected. The cost per lineal foot for an even span is practically the same as for a lean-to of the same length and width. In the lean-to, in order to get the sufficient bench and walk space inside, it is necessary to carry the roof to a point much higher than in the even span. The extra framework and material for the roof cost a good deal, yet add practically nothing to the efficiency of the house." "Heating of greenhouses is best done by hot water, and in a small house the pipes may well be connected with the heating system used for the dwelling, if the greenhouse and the home are within any sort of reasonable distance from each other. For large houses, or ranges of several houses together, the independent heating plant is necessary. Steam is used for heating by commercial florists, but it is economical only on a large scale."