1 00 LADIES' FLOWER GARDENER. 



privcs the plant of certain properties necessary to its perfection, 

 but not essential t o its life. These differences in the processes by 

 which oxygen gas is alternately consumed and evolved, during 

 the vegetation of plants in sunshine, are so manifest, both in their 

 nature and effects, as to satisfy the ascription of a name to th6 

 latter process distinct from that given to the former. It might, 

 perhaps, be denominated the chemical process, in contradistinc- 

 tion to that named physiological. 



" It would contribute much, we think, to simplify our inquiries 

 concerning vegetation, to bear in mind these distinctions ; to con- 

 eider the one process as accomplished by the agency of the air, 

 and essential to the life and growth of the plant ; the other, as 

 subordinate, depending on the agency of light, and though neces- 

 sary to the perfection of vegetation, yet not essential to its exist- 

 ence. In this manner each process may be followed out sepa- 

 rately, both in regard to its immediate effects and remoter con- 

 sequences, without clashing with the other ; and the apparently 

 discordant and even contradictory phenomena which on a first 

 view they seem to exhibit, may be reconciled, and considered, not 

 less in theory than in fact, as conspiring together to form one 

 harmonious and perfect wnole." 



After these explanations, little need be added respecting the 

 snpply of pure air to domestic greenhouses. The deterioration 

 of the atmosphere in the case is daily counteracted by an oppo- 

 site process of purification, so that amidst the vicissitudes of per- 

 petual change, the air is maintained in a state of nearly uniform 

 composition and purity, and serves over and over again for all the 

 purposes of vegetation. It may, however, be stated, to prevent 

 misconception, that the more pure the air of the apartment, the 

 plants will have the better chance of thriving, because there must 

 necessarily be an interchange to some extent betwixt the air of 

 the room and the case, in consequence of the daily expansion 



