James Wimshurst (1832-1903), was an English inventor, engineer and shipwright. Though Wimshurst did not patent his machines and the various improvements that he made to them, his refinements to the electrostatic generator led to its becoming widely known as the Wimshurst machine.
1832 April 13th. Born in Poplar, the son of Henry Wimshurst, a shipbuilder of Ratcliffe Cross Dock. Wimshurst was educated at Steabonheath House in London and became an apprentice at the Thames Ironworks until 1853 with James Mare.
1865 Married Clara Tribble.
1865 After Wimshurst was transferred to Liverpool, he worked at the Liverpool Underwriters' Registry.
1874 Joined the Board of Trade as a chief shipwright surveyor at Lloyds.
1890 Became the Board of Trade's representative at an international conference in Washington.
Wimshurst dedicated large amounts of his free time to experimental works. Besides his electrical activities, he invented a distinctive vacuum pump, a device to indicate ship stability and methods for electrically connecting lighthouses to the mainland.
1878 Began to experiment with electrical influence machines for generating electrical sparks for scientific and entertainment purposes.
Beginning in 1880, he became interested in electrostatic machines of the influence type. His house in Clapham, England, had a versatile workshop which had a wide variety of tools and devices for electric illumination. Wimshurst constructed several of the known types of electrostatic generators, such as those created by W. Nicholson, F. P. Carre and W. T. B. Holtz. To these predecessors, Wimshurst made many modifications with the result known as the Holtz-Wimshurst machine.
Shortly afterwards, Wimshurst developed a duplex machine. The device had two disks turning in opposite directions, with metallic conducting sectors on the surfaces of each. Compared to its predecessors, this machine was less sensitive to atmospheric conditions and did not require an electric power supply. This form of the machine was also improved by other developers (such as the Pidgeon machine developed by W. R. Pidgeon, which increased the electrical induction effect and its electrical output).
1882 Developed his Cylindrical Machine.
1883 His improvements to the electrostatic generator led to the device being widely known as the Wimshurst machine.
In 1885, one of the largest Wimshurst machines was built in England (and is now at the Chicago Museum of Science and Industry).
In 1889 Wimshurst became a member of the Institution of Electrical Engineers.
In 1891, he reported a machine that generated high-tension alternating currents.
1896 His multiple-disk machines (up to 8 disks) found a new use as Roentgen ray generators for radiography and electrotherapy.
1889 For his contribution to medical science, he was elected a Fellow of the Royal Society.
1903 January 3rd. Died died in Clapham, at the age of 70.
1903 Obituary [1]
JAMES WIMSHURST, born on the 13th of April, 1832, was the son of Mr. Henry Wimshurst, who was the first successfully to apply the bladed screw propeller to steamships, and who designed, built, and owned the two first screw-propelled vessels, the Archimedes and the Novelty.
Mr. James Wimshurst was apprenticed to shipbuilding and engineering at the works of the late Mr. Joseph Mare, now the Thames Iron Works, Limited.
Upon completion of apprenticeship he was appointed to the staff of Lloyds Registry of Shipping. After some years he left Lloyds to take up an appointment as Chief of the Staff of the Liverpool Underwriters Registry, and resigned this position, after ten years, to join the Board of Trade as Chief Shipwright Surveyor in the Consultative Department at Whitehall, a post from which he retired three years ago, shortly after reaching the age limit.
During the whole of his career Mr. Wimshurst had devoted the greater part of his leisure time to scientific and mechanical research, and in all houses in which he lived had fitted up large workshops, equipped with benches, lathes, and other tools driven by power, and it was there that he made with his own hands the various devices and apparatus which he invented and with which his name will always be associated. Whilst taking the keenest interest and closely following up the latest scientific and mechanical inventions of all kinds, the subject in which he mostly interested himself was very high-tension electricity, and for the last twenty years of his life he always had some dozen or twenty induction or influence machines of all sorts and kinds in his workshops to experiment upon.
In 1881 a description was published in Engineering of a new type of influence electrical machine, and, being interested, he immediately made one from the written description, but not being contented with the results, he built an improved form of machine of the Carre type. Later he designed and built several machines of the Holtz type, but having the fixed plates supporting the armature cut of rectangular shape and differently coupled; both of these alterations were found greatly to increase the output, and to rectify the difficulty of getting mixed poles. Some of these machines were very large and powerful, and in their day exceeded all others in both efficiency and size. They were fully described in Engineering at the time, and are generally known as Wimshurst's Improved Holtz Machine.
Shortly after this, Mr. Wimshurst designed the well-known influence machine bearing his name, having two plates rotating in opposite directions, this type of machine being remarkable for the great output, the ease with which it excites itself, and its simplicity of construction. It would be difficult to overestimate the value of such a machine in the laboratory or the lecture theatre on account of its great reliability in exciting itself, and it is a matter of interest to note that Mr. Wimshurst hit upon the exact and right proportions in the design of his first machine, such as are found even to this day to be most efficient. His inventive nature led him to design many other forms of this same machine, having cylindrical plates, radial arms, or double coating with paraffin, double plates laid against each other on the same driving boss. All these were tried, but to no practical advantage, and were dropped. It may be mentioned that the greatest regret and disappointment experienced lay in the fact that he did not patent the invention, and therefore had no control over the design and manufacture of the machines as he would have liked to have, not from a financial point of view, but merely to see that none but well-fitted and well-designed machines were made for sale, for his thoroughly sound engineering mind could not view with indifference much of the trashy and defective apparatus that he saw sold to the public. The best proportions having been ascertained, larger and larger machines were constructed. Then, after the discovery of the Rontgen-tube and X-rays, when applying a tube to the terminal of the machine, it was found to be fully illuminated, and a further field for research was thus opened out. The influence machine is found to be of great value for screen work, giving a steady light with considerable penetration, and with entire immunity from the very dangerous X-ray burns which are possible in using the heavy current from battery and coil.
Another highly important application of the Wimshurst machine is the production of exceedingly high-tension brush discharges, which are found to be very efficacious in the cure or reduction of lupus, rodent ulcer, cancer, and. consumption. Most large hospitals are equipped with the Wimshurst machine, and in the United States, especially, the machine is used extensively.
Mr. Wimshurst throughout his career devoted his day hours to the business of shipbuilding and engineering, but the whole of his leisure he gave up to experimental research ; nothing gave him greater pleasure than to work with and to entertain and help his scientific friends in his workshops. He was a most original thinker, and was always at work designing apparatus, taking the greatest pleasure in endeavouring to test the truth of the various theories of the day.
He was a Fellow of the Royal Society, a Member of Council of the Physical Society, Member of Council of the Rontgen Society, Member and one of the Managers of the Royal Institution, Member of the Institution of Naval Architects, Hon. Member of the Institution of Marine Engineers. He was exceedingly simple in his tastes and mode of living, most generous and hospitable, a good friend to a great number of young men whom it was his greatest pleasure to assist. His loss will be regretted by these and by his large circle of friends.
Mr. Wimshurst was elected a Member of the Institution of Electrical Engineers on the 10th of June, 1889.