BOTANY. 373 



growth to prepare for the winter; and though trees might do some good, yet 

 a rank growth of something got up for the occasion might do more. Hops 

 climb high; they are good absorbents, and of a rank growth; but there were 

 objections to hops on account of stakes, poles, etc. I recollected that I had 

 often seen sunflowers growing about the cabins in the West, and had heard, 

 in explanation, that it was " healthy" to have them. 



The theory of this is as follows : The ague and fever poison is set free dur- 

 ing the process of vegetable decay, which poison is absorbed by the rank- 

 gi'owing sunflower, again elaborated into vegetable matter, and so retained 

 until cold weather sets in. The result of the experiment is thus narrated : 



Finally, I resolved to make the experiment at the risk of spoiling the looks 

 of a beautiful lawn. Accordingly, in the fall of 1855, the gardener trenched 

 up, to the depth of two and a half feet, a belt about forty-five feet broad 

 around the observatory on the marshy side, and from one hundred and fifty 

 to two hundred yards from the buildings. The conditions of the theory I 

 was about to try, required rich ground, tall sunflowers, and a rank growth. 

 Accordingly, after being well manured from the stable yard, the ground was 

 properly prepared, and planted in sunflowers in the spring. They grew 

 finely; the sickly season was expected with more than usual anxiety. 

 Finally it set in, and there was shaking at the president's house, and other 

 places, as usual ; but, for the first time since the observatory was built, the 

 watchmen about it weathered the summer clear of chills and fevers. These 

 men, being most exposed to the night air, suffer most, and heretofore two 

 or three relays of them would be attacked during the season; for as one 

 falls sick, another is employed in his place, who, in turn, being attacked, 

 would in like manner give way to a fresh hand. 



REGULARITY OF NATURAL FORMS. 



A correspondent of the London Athenaeum presents the following curious 

 speculation on the above subject : 



" This phenomenon has always appeared to me to be of a veiy astonish- 

 ing nature, and its explanation has hitherto been unattempted. I would, 

 however, endeavor to point out the ways by which the forms of plants, etc., 

 can be determined, taking care, however, to avoid the error of endowing 

 mere matter with the properties of mind an obvious fallacy, and one which 

 it behoves all rational physical inquirers to guard against. It is impossible 

 that either gravity or electricity, or the union of the two, can alone regulate 

 the various forms to be found in the simplest weed. Some other influence 

 or influences must come into action, and what this or these must be I will 

 now endeavor to show: 1. Different kinds of vegetable matter doubtless 

 have different properties ; and the vital force acting upon these may produce 

 the forms we see, without any other influence; or 2. The atmosphere, or 

 some far more attenuated medium, may act as a kind of mould in which 

 the various parts of plants are formed, different vegetable substances pene- 

 trating this universal mould according to their various qualities, and thus 

 assuming different forms, being expanded and propelled probably by the 

 vital and solar forces respectively. It cannot, I think, be doubted, that all 

 considerations on this subject are, however crude and hypothetical, of some 

 value, inasmuch as our present knowledge respecting these matters is so 

 very limited and unsatisfactory. It is found that the elements of future 

 existence are more or less of a circular shape; all roots and bulbs, as also 



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