Born at Greenwich, England, in 1850, the second son of John Fletcher Hargrave and Ann, née Hargrave, Lawrence was educated at Queen Elizabeth's School at Kirkby Lonsdale, Westmoreland. At the age of 15 he sailed to Australia in the La Hogue to join his father, who had moved, to New South Wales in 1866 to pursue a legal career.
Lawrence was destined to follow in his father's career footsteps but he failed his matriculation and in 1867 was apprenticed in the engineering workshops of the Australasian Steam Navigation Company. The cause of his failure is usually seen as his circumnavigation of Australia as a passenger in the schooner Ellesmere soon after his arrival in the colony rather than spend time in study.
The circumnavigation seems to have awakened in Lawrence an interest in exploration and scientific discovery because over the next decade he joined several expeditions to New Guinea, beginning with the ill-fated journey of the brig Maria which sank with great loss of life off the coast of Queensland.
He joined Macleay's Chevert expedition, leaving it prematurely to join Octavius Stone in the Ellengowan. Although regarded as the expedition's engineer, Hargrave made detailed notes of his observations of people, their homes, habits, technology and language.
His last expedition to New Guinea was as engineer to the Italian naturalist, Luigi Maria d'Albertis aboard the launch Neva. Hargrave mapped the Fly River and collected specimens of scientific interest. He was forced to surrender these specimens to d'Albertis.
Upon his return to Sydney he was employed briefly in the foundries of Chapman & Company before becoming an 'extra observer' at the Sydney Observatory measuring double stars, observing the transit of Venus and making observations on the atmospheric consequences of the Krakatoa eruption.
Following the death of his father Lawrence inherited a considerable landholding on the south coast of New South Wales which gave him a sizable income. He resigned from the observatory to concentrate on his scientific experiments into animal motion as a means of ship propulsion. This led him to consider the nature of locomotion through air in the pursuit of the proof of his 'trochoided plane' theory.
He built a number of ornithopters which were tested from the veranda of his Sydney house. These early ornithopters were powered by rubber bands but he realised that greater and more sustained power was required for a man-powered flying machine to succeed.
He began experiments to develop a successful aeronautical engine. In his search he discovered the rotary radial principle and built a model engine to prove its value.
Hargrave did not patent any of his inventions, preferring to disseminate all information to assist aviation experimenters throughout the world. He became well-known throughout the United States, England and Europe as a contributor to the search for the successful aeroplane.
Due to increases in his family and hence costs, allied with the need to find an area with winds favourable to his new line of experimentation, kites, Hargrave moved to Stanwell Park, south of Sydney. Here he designed and built a great variety of kites, ultimately finding that his box or cellular arrangement was the most efficient and stable.
He tested these kites by connecting four together and going aloft for a brief tethered 'flight' over Stanwell Park Beach on 12 November 1894. Once this information was disseminated there appears to have been an improvement in the experimentation in aeronautics.
The stability of the box kite translated into glider form gave some early aeronauts the ability to go aloft long enough to gain practical experience of the effects of winds and gusts on their machines.
The flying machines of Otto Lilienthal, which caught the imagination of many aviation pioneers as well as the general public, were unstable and difficult to control. It is noteworthy that the earliest successful aircraft such as the Voisin and Chanute gliders and the Wright aircraft seem to owe more to the box kite in appearance than to the batwing planform of the Lilienthal gliders. It is well attested that the design of the first successful aircraft in Europe, Santos-Dumont's 14-bis, was a construction based on Hargrave's box kites.
Similarly, there is no question of Hargrave's influence on the Voisin and Farman powered aircraft of the early years of the 20th century. However, a question still remains about the exact influence of Hargrave on Octave Chanute and his gliders and the Wright brothers and their aircraft.
After the successful flight of the Wright brothers in 1903, Hargrave continued with his aeronautical experiments but, in the later years, prior to 1914, spent more time assisting his son Geoffrey with his work on aircraft engines. Geoffrey was killed at Gallipoli in May 1915 and Lawrence succumbed to peritonitis in July of that year.
Many of his models were sent to the Deutsches Museum in Munich and his letters, drawings and diaries sent to the Royal Aeronautical Society in London. Unfortunately many of the models were destroyed during WW2 but those that survived were returned to Sydney in the 1960s and the letters, drawings and diaries later joined these. The Hargrave Collection, so called, is now held in the Powerhouse Museum, Sydney.
During his lifetime Lawrence Hargrave was regarded as one of the great pioneers of aviation. Researchers such as Alexander Graham Bell sought him out and he corresponded with most of the serious aviation experimenters of the time. The indices to his correspondence read like a Who's Who in aviation in the late 19th to early 20th century.