XXXVI.

_WARMING AND VENTILATION._

Open fireplace nearest to natural mode by which earth is warmed and ventilated--Origin of diseases--Necessity of pure air to life --Statistics--General principles of ventilation--Mode of Lewis Leeds--Ventilation of buildings planned in this work--The pure-air conductor--The foul-air exhausting-flue--Stoves--Detailed arrangements--Warming--Economy of time, labor, and expense in the cottage plan--After all schemes, the open fireplace the best.