Henry Joseph Grayson facts for kids

Henry Joseph Grayson (born May 9, 1856 – died March 21, 1918) was a clever scientist and plant grower from Britain who moved to Australia. He is most famous for inventing a special machine. This machine could draw incredibly tiny lines very precisely. These lines were used to make something called diffraction gratings, which help scientists study light.

Early Life and Move to Australia

Henry Grayson was born in a place called Worrall, near Sheffield, in England. His father, Joseph Grayson, was a skilled knife maker. Henry came from a family who grew and sold vegetables.

In the early 1880s, Henry traveled to New Zealand. After a while, he went back to England. He married Elizabeth Clare on August 11, 1886. Soon after, they moved to Victoria (Australia). There, Henry worked as a plant grower.

Discovering a Love for Science

Henry became very interested in science. He joined the Field Naturalists Club of Victoria. He studied botany, which is the study of plants. He also spent time looking at diatoms. Diatoms are tiny, single-celled plants that live in water. They have beautiful, intricate glass-like shells.

Grayson also went to meetings of the Royal Microscopical Society. He became very good at preparing slides for microscopes. Before 1894, he built a machine. This machine could make very tiny, precise lines on glass. The results were excellent for that time.

Work at the University of Melbourne

In 1897, Henry Grayson did some amazing work. He cut very thin slices of plants to study them. Because of this skill, he got a job at the University of Melbourne. He worked in the physiology department, which studies how living things work. His boss was Professor C. J. Martin.

Later, Henry moved to the geology department. This department studies rocks and the Earth. In December 1901, he joined Professor F. T. Gregory on an expedition. They traveled to Central Australia. Professor Gregory later praised Henry in his book, saying Henry did much of the hard work.

In 1910, Henry worked with Daniel James Mahony. They wrote a paper about the geology of the Camperdown and Mount Elephant areas. In the same year, Henry was working under Professor E. W. Skeats at the university. He created a very efficient device for preparing thin sections of rocks. This made it easier to study them under a microscope. A description of this device was published in the Proceedings of the Royal Society of Victoria in 1911.

Inventing the Diffraction Grating Machine

While working at the university, Henry Grayson kept improving his work on making tiny lines. He managed to create an amazing 120,000 lines per inch (about 4,700 lines per millimeter)! These lines are used to make diffraction gratings. These gratings are special tools that can split light into its different colors, like a rainbow. They are very important for scientific research.

In 1900, Henry described his work on this machine. He shared it in a report for a science meeting in Melbourne:

The apparatus I first devised and used was exceedingly simple in principle, and consisted essentially of a fine steel screw and wedge of glass, the incline of the latter bearing some definite ratio to the pitch of the former. This glass wedge traveled along a bed, or base plate, also of glass, being kept in position by means of a slot cut along its surface. As the wedge was propelled forward by the screw it raised a vertical plate, accurately adjusted at right angles to the base plate, and as free as possible from movement other than that imparted to it by the wedge. To this vertical plate the slide, or disc to be ruled upon, was attached by means of a suitable cement. A platform for a sliding diamond carriage bridged the base-plate and wedge at a suitable height, being of course arranged transversely to and in front of the vertical slide.

From then on, much of his time was spent building a special machine. This machine was called a dividing engine. It was designed specifically for making diffraction gratings.

Later Years and Legacy

In 1913, Henry Grayson moved to the Natural Philosophy department at the university. This department was led by Professor T. R. Lyle. Henry was allowed to spend all his time working on his amazing machine.

In July 1917, he gave a presentation about his machine to the Royal Society of Victoria. A full description of the machine, with pictures, was published in the society's Proceedings that year. In the same year, the University of Melbourne gave him the David Syme Research Prize. This was a special award of £100 for his important research.

Henry Grayson passed away in Clyde from heart disease. He left behind his wife but no children. His work on the diffraction grating machine was a significant contribution to science.