VERNAL FLOWERS. 
195 
eauses. But ii should be the main object of education to teach youth in reject, to 
aeek the connection between cause and effect ; and especially, to look throug'Jj 
second causes to the Great Being Avho is the Mrst Cause of all — "himself nt)- 
caused." But to return to the question, " What causes Spring ?" or, to state it in 
another form, By what means does the Almighty produce the changes which tL'a 
season presents ? To answer this, we must refer to astronomical geography, which, 
pointing out the course of the sun, shows us, that having journeyed to his utmoa*^ 
southern boundary, he returns, crosses the equator, and with rapid strides advance.* 
toward the northern hemisphere, beaming more directly upon us, and increasing 
the temperature of the atmosphere ; — to chemistry we owe our knowledge of tht 
effects of caloric on bodies ; — physiological botany shows us the sap, or vegetablt 
blood, expanding by the influence of caloric, and every exhaling and inhaling orgar 
of the plant commencing operations under the same powerful influence. The 
earth, released from the icy bonds of frost turns kindly to the mute but living 
children of her bosom, and imparts the maternal nourishment, wliich, rushing 
through every fiber of the vegetable being invigorates it with health and strength. 
296. From the .first appearance of vegetation in the spring, 
until the commencement of winter, nature presents an ever- 
varjing scene. The phenomenon of the flowering of plants is in 
many respects similar to that of the putting forth of leaves/^ in 
both, the same causes either hasten or retard this period. The 
putting forth of leaves, and the blossoming of flowers, difler, 
however, in one circumstance : the leaves begin by the upper 
leaf-buds ; the flowers generally by the lower flower-buds ; 
stipes^ panicles^ and thyrses^ begin to blossom gradually from 
the base to the summit ; cymes and umbels blossom from the 
outside to the center. 
297. In plants of the north transported to the south, the 
period of the putting forth of leaves and blossoming is hast- 
ened ; in those of the south carried to the north, it is retarded. 
Even in their native soil this period varies in some degree in 
different seasons. With greater warmth of temperature, we 
have an earlier appearance of vegetation ; yet in general this 
variation is so slight, that botanists are able by observation to 
flx with a sufficient degree of accuracy the time of the flower- 
ing of plants in particular latitudes and climates. The progress 
of vegetation varying little from latitude 40° to 43° north, the 
remarks we make on this subject may apply to that region of 
country extending from the mouth of the Hudson on the south, to 
the mouth of the Mohawk on the north ; eastward to the Atlan- 
tic, and westward to the Pacific Ocean. In Ohio and the west- 
ern part of New York, the climate on account of the influence 
of the lakes, and the cold eastern winds from the Atlantic being 
broken by ranges of mountains, is milder, and vegetation is 
somewhat earlier, than in New England in the same latitude. 
298. In some cases a plant puts forth leaves and blossoms 
• Foliation. 
296. Changes in vegetation — Putting fortli of leaves and blossoming of flowers agree in some respects, 
differ in others. — 297. Plants of the north transplanted to the south, and tlie reverse — Remarks on tJis 
progress of vegetation. 
