THE FARMER AT HOME. 15] 



Decondello and others, and repeated by Leibig, it is established be- 

 yond all question that the roots of plants throw oft' an excrement 

 during the progress of their growth, and that the excrement of each 

 plant is peculiar to itself. And further, that the presence of such 

 matter in a soil, impedes the growth of plants of the same kind, 

 whilst in some instances it becomes a source of nourishment to others. 

 This fact is used as an argument, among other known reasons, in 

 favor of a rotation of crops. And much will depend upon the nature 

 and character of the soil itself as to what time should elapse before a 

 certain crop may be successfully repeated. 



EXHALATION. Generally speaking, denotes effluvia or steams, 

 which arise from the surface of the earth, or other bodies, in the form 

 of vapor. Plants and flowers afford a grateful exhalation, provided 

 their fragrance be not too stroig ; hence they should never be placed 

 in confined apartments, as instances have occurred of persons being 

 almost suffocated, by sleeping in rooms where quantities of fresh 

 flowers were exposed. In serene weather, however, fresh plants or 

 evergreens (but by no means flowers) may be strewed with advan- 

 tage, during the day, in the apartments of valetudinarians ; as such 

 vegetables, especially in sunshine, generate a vital air, which produces 

 salutary effects on the lungs. 



The exhalations arising from vast numbers of burning candles, as 

 also from the breath of many persons respiring in the same room, are 

 peculiarly unwholesome to weak and consumptive habits. This incon- 

 venience may, however, be remedied by means of conical tubes, the 

 funnels or broad ends of which should be placed so as to communicate 

 in or above the windows, with the open air ; thus the latter will be 

 impelled into the rooms with considerable force, and ventilate them 

 more effectually, and at much less expense, than is accomplished by 

 fumigations or other methods. The vapor arising from charcoal is 

 particularly hurtful, and, in close apartments, often productive of fatal 

 accidents. The greatest precaution is therefore requisite, when char- 

 coal is employed for culinary or domestic purposes. In a similar 

 manner humid air of every kind is very detrimental to health ; and 

 we seriously reprobate the keeping of damp linen, wet clothes, and 

 even wet umbrellas, in dwelling-rooms ; as, by paying* due attention 

 to this circumstance, many serious accidents might easily be pre- 

 vented. 



EXOTIC. An appellation for the produce of foreign countries. 

 Exotic plants are such as belong to a soil and climate entirely difler- 

 ent from the place where they are raised, and therefore can be pre- 

 served for the most part only in green-houses. Exotic plants of the 

 hot climates are very numerous, and require the utmost attention of 

 the gardener. Even if they can be brought to blossom, it is rare that 

 they produce fruit, and still more rare that the seeds ripen. It is 

 only by care and accurate observation of their nature and wants, that 



