164 Mississippi Valley Horticultural Society. 



membered, such 'dunes should never be stripped of their natural groAvths, 

 nor should they ever be cut, torn or plowed; keep them covered with vege- 

 tation and thc\' may be controlled. 



SANITARY AND HYGIENIC RELATIONS. 



On coming to the discussion of this branch of the subject, the first impres- 

 sion was that it might be difficult to see wherein the sanitary differed from 

 the hygienic, since both words are derived from radicals that convey the idea 

 of health. 



The difficulty was solved, however, by a more careful study of their deriva- 

 tion. Sanitary, or that which pertains to health, from sawjYas, health, appears 

 to be a more generic term, since it is applicable to all that relates to health, 

 whether good or bad, as it is sometimes used in the sense of dejjreciation — 

 thus the sanitary condition of a place may be esteemed bad, and capable of 

 amendment. 



Hygienic, from Hygeia, the Goddess of Health, or health itself, may be said 

 to refer to that which produces and protects our health — it is preservative 

 and should not be used in a bad sense. 



Thus the hygienic relations of forests must refer solely to the influences 

 which trees may contribute to the healthfulness of a community or country, 

 while the sanitary relations may also include all those results connected with 

 our health or disease that are traceable to the influences exerted upon the 

 animal frame by the presenc^e and proximity of forests. 



That forests do exert an important influence upon the sanitary conditions 

 of a Oountry can not be doubted, and it must be admitted that their relation 

 to public health is not alwiys favorable. 



It is especially true that too much shade in the immediate vicinity of our 

 dwellings, so as to exclude the direct access of sun and air, is productive of 

 insalubrious results. 



Forests having been proved to be reservoirs and retainers of moisture, and 

 being known to exercise an important influence upon the climate of a coun- 

 try, they can not fail to exert a sanitary influence. Where they occupy exten- 

 sive tracts of low and level land, their retention of superabundant moisture, 

 by obstructing its free escape by evaporation or by the natural channels, and 

 causing it to be retained among the accumulated remains of vegetation, may 

 undoubtedlj'- produce disease, and in such cases their influence upon the 

 sanitarj^ conditions is unqiiestionably bad. On the other hand, and in other 

 situations, the admitted influence of forests upon the continuous supply of 

 pure and healthful water, produces the most happy and important hygienic 

 effects upon all animal life. 



To a certain extent, also, and in particular localities, masses of forests, and 

 even belts of trees, may exert a most happy hygienic effect by cutting off' the 

 malarious exhalations arising from marshy districts that would otherwise 

 prove very injurious to the health of neighboring communities. 



