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THE POPULAR SCIENCE MONTHLY. 



of their noxious properties. An instance 

 of this recently befell a newspaper corre- 

 spondent in Armenia. Having drunk some 

 honey-sweetened water he was shortly after- 

 ward seized with headache, vomiting, cold- 

 ness of the extremities, and temporary 

 blindness, followed by a cataleptic state. 

 Inquiry showed that the honey had come 

 from the Boturu Valley, where hemlock and 

 henbane grow abundantly. Mr. Thurber 

 points out the singular coincidence that 

 more than 2,000 years ago Xenophon's sol. 

 diers met with a similar accident in the same 

 locality. 



Beavers in Colorado. Mr. E. A. Barber, 

 connected with Prof. Hayden's survey of the 

 Territories, in the year 1874 had an oppor- 

 tunity of examining, on the banks of the 

 Grand River, in Northwestern Colorado, the 

 work of a colony of beavers. His observa- 

 tions, as published in the American Natu- 

 ralist, are highly interesting, and we present 

 the substance of them to our readers. He 

 was first apprised of the vicinity of the bea- 

 vers by watching a timber-shoot or clear- 

 ing scooped out from a willow -brake to 

 the water. Through this slide Mr. Barber 

 passed into a grove of slender willows form- 

 ing a thicket. About fifty feet from the 

 river was a circular clearing where the ani- 

 mals had been at work ; here the trees were 

 larger, and many of them had been cut off 

 obliquely within six inches of the ground 

 the logs had been hauled away. Farther on 

 larger trees had been felled, which were 

 still lying there, most of them measuring 

 six and eight inches diameter, and one at 

 least fourteen inches. The wood had been 

 gnawed around the circumference, a few 

 inches from the base, the deepest cutting 

 having been done on the side next the water, 

 so that the tree might fall in that direction. 

 " I noticed," writes Mr. Barber, " that, wher- 

 ever there were trees which had been felled 

 some time past and fallen in the wrong di- 

 rection, the newer work had been accom- 

 plished, without exception, in a systematic 

 manner, all of the logs being cut so as to 

 fall toward the dam. As I passed along 

 the bank of the stream, I observed about 

 ten timber-shoots running parallel at right 

 angles to the course of the current, and sep- 

 arated by about fifteen feet. The larger 



trees had been cut near the water and above 

 the dam for the purpose of floating them 

 down, to save the labor of dragging from 

 the interior. ... I picked up several chunks 

 of wood, six or eight inches in diameter and 

 about as much in length, the ends being 

 obliquely parallel ; these had probably been 

 prepared to fill up chinks in the walls of the 

 dam. The trees had been, for the most 

 part, cut into sections averaging ten feet in 

 length, and the branches and twigs had been 

 trimmed off as cleanly as a wood-chopper 

 could have done them. Along the banks of 

 the White River, some weeks before, I no- 

 ticed several artificial canals which had been 

 dug out in the absence of natural side-chan- 

 nels in the river. These were designed for 

 floating down logs. One canal was four 

 feet in width, seven in length, and several 

 feet deep." 



How the Spiders spin. Happening to 

 be in the fields during a sunshiny day in 

 autumn, while a gentle wind was blowing, 

 the Rev. H. C. McCook, of the Philadelphia 

 Academy of Natural Sciences, took occasion 

 to observe the aeronautic flights of the young 

 spiders, whose silken filaments were floating 

 from every stalk of grass. He found that 

 many of the young arachnids mostly of the 

 family Lycosidce, which are ground-spiders 

 selected the tops of the fence-posts as their 

 starting-point. Having reached this " point 

 of vantage," the spider always turned the 

 face toward the wind. Then the abdomen 

 was elevated to an angle of about 45, and at 

 the same time the eight legs were stiffened, 

 thus pushing the body upward. From the 

 spinnerets at the apex of the abdomen a sin- 

 gle thread was ejected and rapidly drawn out 

 by the breeze, often to the length of five or 

 even six feet. Gradually the legs were in- 

 clined in the direction of the breeze, and the 

 joints straightened out. The foremost pair 

 of legs sank almost to the level of the post. 

 Suddenly the eight claws were released and 

 the spider mounted with a bound into the air, 

 and was quickly carried out of view. The 

 author distinctly noticed that at the instant 

 of beginning its aerial journey, the spider 

 would make an upward spring. He was also 

 so fortunate as to be able to follow the flight 

 of a spider for a distance of about eighty 

 feet, and observed that the position of the 



