NEED A JOB?National Companies Seek Local Help Now. | |
 If you'd prefer not to receive these, Unsubscribe Here. Secure Home Profits | 63 East 11400 South #224 | Sandy, UT 84070 |
Despite the operational and maintenance obstacles, construction of the pump enabled Boyle to conduct a great many experiments on the properties of air, which he later detailed in his New Experiments Physico-Mechanicall, Touching the Spring of the Air, and its Effects (Made, for the Most Part, in a New Pneumatical Engine). In the book, he described in great detail 43 experiments he conducted, on occasion assisted by Hooke, on the effect of air on various phenomena. Boyle tested the effects of "rarified" air on combustion, magnetism, sound, and barometers, and examined the effects of increased air pressure on various substances. He listed two experiments on living creatures: "Experiment 40," which tested the ability of insects to fly under reduced air pressure, and the dramatic "Experiment 41," which demonstrated the reliance of living creatures on air for their survival. In this attempt to discover something "about the account upon which Respiration is so necessary to the Animals, that Nature hath furnish'd with Lungs", Boyle conducted numerous trials during which he placed a large variety of different creatures, including birds, mice, eels, snails and flies, in the vessel of the pump and studied their reactions as the air was removed.[3] Here, he describes an injured lark: …the Bird for a while appear'd lively enough; but upon a greater Exsuction of the Air, she began manifestly to droop and appear sick, and very soon after was taken with as violent and irregular Convulsions, as are wont to be observ'd in Poultry, when their heads are wrung off: For the Bird threw her self over and over two or three times, and dyed with her Breast upward, her Head downwards, and her Neck awry.[4] By the time Wright painted his picture in 1768, air pumps were a relatively commonplace scientific instrument, and itinerant "lecturers in natural philosophy"—usually more showmen than scientists—often performed the "animal in the air pump experiment" as the centrepiece of their public demonstration.[5] These were performed in town halls and other large buildings for a ticket-buying audience, or were booked by societies or for private showings in the homes of the well-off, the setting suggested in both of Wright's demonstration pieces.[6] One of the most notable and respectable of the travelling lecturers was James Ferguson FRS, a Scottish astronomer and probable acquaintance of Joseph Wright (both were friends of John Whitehurst). Ferguson noted that a "lungs-glass" with a small air-filled bladder inside was often used in place of the animal, as using a living creature was "too shocking to every spectator who has the least degree of humanity".[7]
Post#96503-64895, Wa, DC 2OO90-24189
No comments:
Post a Comment