Proceedings of the British Association. S4B 



most of the graminivorous birds, can find nothing to support them in 

 the winter season ; and, consequently, the migration of the feathered 

 tribes is here much more general than in the countries of Europe ly- 

 ing under the same parallel. The principal cause of this great dif- 

 ference between the climates of tlie eastern and western districts, 

 may be ascribed to the configuration of the coast land, which de- 

 tains the ice in its bays and gulfs, and this, in melting, materially 

 depresses the summer heat. The decrement in the mean annual 

 heat, corresponding to the increase in latitude, is greater in North 

 America than in Europe, and there exists a wider difference between 

 the temperatures of summer and winter. Dr. Richardson then con- 

 cluded this introductory portion of his report, by details concerning 

 the temperatures which had been observed at different places in the 

 country under consideration. 



Mr. Rootsey exhibited specimens of sugar, malt, and an ardent 

 spirit, which he had extracted from mangel wurzel, and considered 

 that this root might, under certain circumstances, be grown to great 

 advantage in this country, for the purposes of manufacturing the 

 above articles. 



Mr. G. Webb Hall read a communication " On the Acceleration 

 of the Growth of Wheat." After pointing out the advantages which 

 might accrue to agriculture from the attention given by scientific 

 men to certain subjects with which it was connected ; and the abso- 

 lute necessity which now existed for making the most extensive and 

 careful investigations concerning many points of great importance to 

 the success of agriculture, he proceeded to call the attention of the 

 Section to a statement of facts, by which it would be seen that the 

 usual period allotted to the occupation of the ground for a crop of 

 wheat might be very materially abridged. At an average, this might 

 be estimated at ten months, though twelve, and even thirteen, were 

 not unusual, and eight might be considered as the shortest period for 

 the ordinary winter wheat. By a selection of particular seed, and 

 a choice of peculiar situation, wheat sown early in March has been, 

 on different occasions, ripened before the middle of August, a period 

 scarcely exceeding five months. Mr. Hall considers it an unques- 

 tionable law of vegetation, that the offspring of a plant of early ma- 

 turity itself, seeks to become so likewise, even when placed in un- 

 propitious circumstances, and that it recedes with reluctance from 

 the condition of its parent. Hence the seed of a crop which has 

 been ripened in five months has a better prospect of producing 



Vol. XXXI.— No. 2. 44 



