An Experiment on a Bird in the Air Pump

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An Experiment on a Bird in the Air Pump

Joseph Wright of Derby, 1768

Oil-on-canvas

183 × 244 cm, 72 × 94½ inches

National Gallery, London, England

An Experiment on a Bird in the Air Pump is a 1768 oil-on-canvas painting by Joseph Wright of Derby which depicts a recreation of one of Robert Boyle's air pump experiments.

Contents 1 Background 2 Painting 3 References in other work 4 Notes

[edit] Background

In 1659, Robert Boyle had commissioned the construction of an air pump (now known as vacuum pump and at the time also referred to as a "pneumatic engine"). The air pump had been invented by Otto von Guericke in 1650, but the cost meant that scientists had shied away from constructing the apparatus. Boyle, the son of the Earl of Cork, had no such worries - after its construction he quickly donated the initial 1659 model to the Royal Society and had a further two redesigned machines built for his own use. Aside from Boyle's three pumps there were probably no more than four others in existence during the 1660s: Christian Huygens had one in The Hague, Henry Powers may have had one at Halifax, and there may have been pumps at Christ's College, Cambridge and the Montmor Academy in Paris. Boyle's pump was mostly constructed by Robert Hooke and as well as being expensive, it was complicated, temperamental, and difficult to operate.^[1] Nevertheless it allowed him to conduct a great many experiments on the properties of air, the most dramatic of which was the demonstration of the reliance of living creatures on air for their survival. This formed "Experiment 41"; in an attempt to discover something "about the account upon which Respiration is so necessary to the Animals, that Nature hath furnish'd with Lungs", Boyle placed a large number of different animals: birds, mice, eels, snails and flies in the vessel of the pump and studied their reactions as the air was removed. Here, he describes an injured lark:^[2]

...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.

—Robert Boyle, New Experiments, 1660

By the time Wright painted his picture in 1768, air pumps were relatively commonplace scientific instruments and the "animal in the air pump experiment" used more often than not as the centrepiece of a demonstration by itinerant "lecturers in natural philosophy", who were often more showmen than scientists.^[3] James Ferguson, Scottish astronomer and probable acquaintance of Joseph Wright (since they were both friends of John Whitehurst), writes that a "lung-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".

[edit] Painting

Wright's painting forms part of a series of candle-lit nocturnes that he produced in the 1760s. The first piece Three Persons Viewing the Gladiator by Candlelight which he painted in 1765, showed three men studying a model of the "Borghese Gladiator" and was greatly admired, but his next painting A Philosopher giving that lecture on the Orrery, in which a lamp is put in place of the Sun (normally known by the shortened form A Philosopher Giving a Lecture on the Orrery or just The Orrery) caused a greater stir, as it replaced the Classical subject at the centre of the scene with one of a scientific nature. The Orrery was painted without a commission, probably with the expectation that it would be bought by Earl Ferrers, an amateur astronomer who had an orrery of his own, and with whom Wright's friend, Peter Perez Burdett, was staying while in Derbyshire. Ferrers did purchase the painting and it is now held by Derby Museum and Art Gallery.^[4]

An Experiment on a Bird in the Air Pump followed in 1768, the chaotic experiment contrasting with the orderly scene from The Orrery. It shows a white cockatoo fluttering in panic as the air is slowly withdrawn from the vessel by the pump. The witnesses show various emotions: one of the girls looks on worriedly at the fate of the bird, the other is too upset to continue observing and is comforted by her father; two gentlemen and a boy look on with interest, while the young lovers to the left of the painting are interested only in each other. The scientist himself looks directly out of the picture, as if challenging the viewer to make the decision on whether the pumping should continue killing the bird or whether the air should be replaced and the cockatoo saved.^[5] The single light source creates a chiaroscuro effect, and the boy at the rear is drawing the curtains to block out the light from the full moon. To one side of the boy the cockatoo's empty cage can be seen on the wall. The scientific subjects of Wright's paintings from this time are meant to appeal to the wealthy scientific circles in which he moved; while never a member himself he had strong connections with the Lunar Society and Josiah Wedgwood later commissioned paintings from Wright.^[6] The painting was presented to the National Gallery in London by Edward Tyrell in 1863.^[7]

[edit] References in other work

The cover of the book, The Science of Discworld, by Terry Pratchett, Ian Stewart and Jack Cohen is a tribute to the painting, by artist Paul Kidby. The painting's characters are replaced by the book's protagonists.

[edit] Notes