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PERFECT SOCIETIES OE INSECTS. 



terminated in a hook, to which he fastened a hair with a 

 small square of very thin paper at the other end ; this was 

 exactly opposite to the aperture, at the distance of about an 

 inch from it. As soon as the apparatus was fixed, the hair 

 with its paper pendulum began to oscillate more or less, the 

 greatest oscillations on both sides being an inch, by ad- 

 measurement, from the perpendicular ; if the paper was 

 moved by force to a greater distance, the vibrations did not 

 take place, and the apparatus remained at rest. He then 

 made an opening in the top of the hive, and poured in some 

 liquid honey ; soon after there arose a hum, the movement 

 in the interior increased, and some bees came out. The os- 

 cillations of the pendulum upon this became more frequent 

 and intense, and extended to fifteen lines or an inch and a 

 quarter from the perpendicular; but when the paper was 

 removed to a greater distance from the aperture, it remained 

 at rest. 



Huber, at the proposal of M. de Saussure, in order to 

 ascertain whether artificial ventilators would produce an 

 analogous effect, got a mechanical friend to construct for him 

 a little mill with eighteen sails of tin. He also prepared a 

 large cylindrical vase, into which he could, at an aperture in 

 the box upon which it was fixed, introduce a lighted taper. 

 In one side of this box was another aperture to represent that 

 of a hive, but larger. The ventilator was placed below, and 

 luted at the points of contact, and anemometers were sus- 

 pended before the aperture. The first experiment was the 

 introduction of the taper, without putting the ventilator in 

 motion. Though the capacity of the vessel was about 3228 

 cubic inches, the flame soon diminished, and went out in 

 about eight minutes, and the anemometers continued motion- 

 less. The same experiment was next repeated with the door 

 shut, with precisely the same result. After the air of the 

 vessel had been renewed, the taper was again introduced, and 

 the ventilator set in motion : immediately, as appeared by 

 the oscillations of the anemometers, two currents of air were 

 established, and the brilliancy of the flame was not diminished 

 during the whole course of the experiment, which might have 

 been prolonged for an indefinite time. A thermometer placed 



