1847.] 



Vegetable 

 kingdom. 



Shade Trees not injured by Gas. 101 



{ Class I. Angiosperms, 

 I —^—' ) Class II. Gyn 

 Phasnosamia, 



/ Ti S Class I. Ano-iosperms, 



( Exogens, < .^, tt n 



° } Class 11. Crymnosperms. 



[ Endogens, ) p. 



Cryptogamia, • 



ass III. Aglumaceous, 

 Class IV. Glumaceous. 



^ Class V. Acrogens, 

 ( Class VI. Thallogens. 



This edition contains a great amount of the most important and 

 desirable knowledge in theoretical and practical botany, and forms 

 a beautiful book of 645 pages. 



The teachers of botany in our higher schools should make 

 themselves familiar at once with the Class Book of Botany, and 

 teach no other than the natural system. Even the imperfect 

 knowledge, too commonly obtained by classes in botany, should 

 be taught on correct principles and from the more perfect system. 

 The books on English grammar, or arithmetic, fifty years old, 

 are not so far behind the times as the works on botany which 

 have been in use till recently. A teacher cannot too soon come 

 up to the improvements of the age. 



The first edition was extensively adopted in the important 

 seminaries of the northern states. The adaptation of the work to 

 a more southern latitude was eagerly desired. This has now 

 been effected. Tlie second edition is certain of a more wide and 

 general use. It will go wherever the other has come to be used, 

 and be hailed as a great improvement. It deserves a place in 

 every library, which is used by those who have any knowledge 

 and taste in this science. 



SHADE TREES NOT INJURED BY GAS. 



It has been supposed that many of the shade trees which are 

 dying and dead in this city, have been injured and killed by the gas 

 which escapes from the conducting pipes. However plausible this 

 view of the subject may appear at first sight, it will nevertheless 

 be found on examination that the trees are injured by other causes. 

 It is true that trees near any establishment where sulphurous acid 

 and other compounds of sulphur escape, vegetation is either de- 

 stroyed or injured more or less. Even the lime from the gas 

 works through which the gas has passed for purification is injuri- 

 ous to plants, especially those which belong to the herbaceous 

 kind; but this lime may be put around the body of fruit and for- 

 est trees without perceptibly injuring them. The trees which are 

 dead and dying in Chapel street, are destroyed by other causes. 



