The principle of the rotary engine was discovered by this Australian pioneer, although later two French builders developed them ingeniously and reliably.

“Lawrence Hargrave”

-Hargrave designed many kites, first enslaved to the ground and then motorized. For this he invented the light rotary engine that we show below.

“Hargrave's rotary engine”

-Photography taken from one of the many apparatus designed by this pioneer.

-In 1910, Lawrence himself donated a collection of his engines (engine models) to the Deustches Museum.

-In 1961, the Museum of Applied Arts and Sciences in Sydney, Australia purchased some models.

-Lawrence Hargrave was born in Greenwich, England in 1850 and in 1872 he moved to Australia in search of fortune. The ship is said to have broken down near Queensland where he decided to settle.

-Being admitted to the Royal Society of NSW in 1877. He also worked at the Sydney Observatory, pursuing the research below.

-Between 1884 and 1892 he made and experimented with monoplane models.

-For posterity he decided to deliver the 176 models to the place where they were exposed to the public.

-The only museum that accepted its terms was the Deustches Technological Museum in Munich.

-Then, during WWII, most of them were destroyed, leaving about 25 devices that were acquired, as has been said, by the Powerhouse Museum in Sydney.

-Apart from the radial engine with three rotating cylinders that is presented in the main text, we now present the double-acting wind turbine, running on steam. From the year 1886.

“Hargrave's 1886 model for flapping wings”

-In 1888, he offers a single cylinder made with copper alloy on a wooden base. This engine is intended for an airplane, with flapping wings as well.

“Lawrence Hargrave model from 1888”

-And in 1889 the three-cylinder rotary, with a propeller blade on each cylinder.

“Hargrave's 3-cylinder rotary engine from 1889”

“Another model for flapping wings”

-Another ornithopter powered by a steam engine and flapping wings. One of the many models that Lawrence designed.

“One of Hargrave's Ornithopteros”

From Appendix 7: We received a schematic drawing of a radial three-cylinder arrangement that we reproduced below for your interest.

“Three-cylinder engine with small scale”

"Engine with the cylinders attached to the blades"

-It is therefore a rotary radial engine running on an elastic gas such as steam.

-Model trials were made around 1890. Lawrence Hargrave was an Australian pioneer.

“Hardgrave model at the Powerhouse Museum in Sydney”