176 



Oil of Indian Corn. — Magnesia. 



Vol. VII. 



water. But a few moments since, I heard a 

 swallow, apparently at some height in the 

 air, utter two shrill notes; on hearing which 

 I observed the whole of the flock quit the 

 water, and rise into the air, so as almost to 

 disappear from the sight. After a short 

 time they returned to hawk for flies, and dip 

 their bodies on the surface of the river at the 

 place they had just before quitted. If the 

 notes were not intended as a warning of ap- 

 proaching danger, I could almost fancy that 

 it was a call for them to partake of a banquet 

 of insects which had suddenly made their 

 appearance elsewhere. 



On mentioning this circumstance to an ob- 

 servant friend, with whom I have had many 

 very agreeable conversations on Natural 

 History, he informed me that when he was 

 lately at Malvern, he had an opportunity of 

 observing the effect which the two notes I 

 have just described, had on a large assem- 

 blage of swallows. They had congregated 

 in great numbers on the roof of a house at 

 that place. The preceding evening had 

 been cold and somewhat frosty, so that early 

 in the morning the swallows were so torpid 

 that he caught two or three of them in his 

 hand, as they rested on the roof near the 

 window of the room in which he slept. While 

 they were in this state he heard two shrill 

 notes from a swallow, and in an instant the 

 whole of them took wing simultaneously, and 

 having made two or three circuits in the air, 

 disappeared altogether. He fancied that 

 these circuits were preparatory to their mi- 

 gration, but they were more probably a notice 

 that food was at hand. At all events it seems 

 clear to me that there is a master or leading 

 swallow, who guides the movements of the 

 rest while they are as usual, congregating 

 previous to their migration. Having men 

 tioned this circumstance, I trust that it will 

 engage the attention of others, so that further 

 light may be thrown on this curious fact in 

 the economy of the swallow. 



Jesse's Gleanings. 



Oil of Indian Corn. — This oil is obtained 

 in the course of the process of making whis- 

 key. It rises in the mash-tubs, and is found 

 in the scum at the surface, being separated 

 either by the fermentation or the action of 

 heat. It is then skimmed off, and put away 

 in a cask to deposit its impurities; after 

 which it is drawn off in a pure state, fit for 

 immediate use. The oil is limpid, has a slight 

 tinge of the yellow color of the corn, and is 

 inoffensive to the taste and smell. It is not 

 a drying oil, and therefore cannot be used for 

 paint, but burns freely in lamps, and is use- 

 ful for oiling machinery. — Sillimaii's Jour- 

 nal of Science and Arts. 



For the Farmers' Cabinet. 

 Magnesia. 



I pray you, Messrs. Editors, give me space 

 for a very short extract from a paper lately 

 read by Professor Johnston, before the High- 

 land and Agricultural Society of Scotland, 

 " On the improvement of oats growing on 

 moss," as I conceive, it will be found inte- 

 resting to your readers, during the present 

 exciting controversy which is being carried 

 on through the pages of the Cabinet. The 

 Professor says, — 



" It is well known to practical agricultur- 

 ists, that oats grown on reclaimed peat or 

 moss lands, are apt to produce much straw, 

 but to yield an ear which is poor and badly 

 filled ; the straw also being soft and void of 

 that hard shining surface, by which ripe oat- 

 straw, grown upon sound land, is generally 

 distinguished. The conclusion we naturally 

 draw, from a knowledge of the effect of an 

 application of clay to these peaty soils, is, 

 that the defect consists not in their contain- 

 ing any noxious ingredients, but in their 

 want of something necessary to the healthy 

 growth and maturity of the plant; which the 

 clay contains, and is able to supply. The 

 first deficiency in oats grown on moss, of 

 wdiich I was made aware w T as, that the ear 

 did not fill, — in such a soil, the acknow- 

 ledged deficiency is in mineral matter, and I 

 therefore considered it likely that the plant 

 found it difficult to procure the mineral sub- 

 stances which are always present in a full 

 and healthy ear. These are chiefly the phos- 

 phates of lime and magnesia, and I conse- 

 quently recommended a trial of bone-dust 

 mixed with certain other substances, which 

 might yield also a further supply of nitrogen, 

 which is known to be necessary to the pro- 

 duction of the seeds of nearly all plants. 

 This mixture contained no magnesia, to sup- 

 ply which, however, it was not improbable that 

 the lime, added to the land might suffice; as 

 very many limestones contain an appreciable 

 admixture of magnesia. These suggestions 

 were carried into effect in a skilful and zeal- 

 ous manner, and the results, in reference to 

 a trial of bones dissolved in sulphuric acid, 

 mixed with a small quantity of nitrate of 

 soda, were thus reported by Mr. Fleming, 'I 

 examined the oats again a few days before 

 they were cut, when I was much satisfied ; 

 the straw appeared to me as stiff and shining, 

 and the ears as well filled, as if they had 

 been grown upon stiff loam; and I consider 

 the same dressing- applied to grain crops upon 

 moss, will insure a good crop of well-filled 

 oats.' So far as a trial on one locality can 

 be relied upon, therefore, we may consider 

 this result exceedingly satisfactory." 



T. Bennet. 



