Janet Taylor (13 May 1804 – 25 January 1870) born Jane Ann Ionn, was an English astronomer and navigation expert. She published various works on astronomy and navigation, founded an academy for the teaching of these subjects, and ran a warehouse focused on the distribution, production and repair of navigational instruments. Her Academy was highly regarded and recommended by the East India Company, Trinity House, and the Admiralty. In recognition of her work, she was awarded medals by the Kings of Prussia and the Kings of the Netherlands, and her rule for calculating latitude from altitudes was described as "ingenious". Taylor was one of the very few women working as a scientific instrument maker in London in the 19th century. Her "Mariner's Calculator", patented in 1834, was dismissed by the Admiralty.
Taylor was born in Wolsingham to Reverend Peter Ionn and Jane Deighton, being the fourth born of the family of eight. Her father was master of the Free Grammar School, which was one of the few north county schools that included navigation in its curriculum, and he allowed Jane Ann to attend both the basic grammar school and theoretical navigation tuition. After her father's death, Jane Ann continued her education with theoretical navigation studies. Her father's passing left her with a good fortune, which she invested wholeheartedly into a career in nautical education, a male dominated field at the time.
When she married George Taylor, a widower with three children, in 1831, she became a stepmother and changed her name to Janet. They moved north of Theobald's Road in London and this is where Janet decided to start her first nautical academy in 1833. This academy was strictly made for merchant service officers. During this time period she published "Luni-Solar and Horary Tables," which discussed calculations that were able to "reduce the lunar distance" that used a formula she derived herself. She continued her path in navigation and in 1834 received a patent for her invention of a Mariner's Calculator. The invention did not get approved by Admiralty, deeming it unworthy for the Lordships Patronage. Later on, she published a second edition of the book, "Principles of Navigation Simplified." Though, the cost of creating the second edition of this book and the Mariner's Calculator put her in a place where she was slowly draining her capital.
Afterwards, she spent some time working on the formula she derived for her first published book to further improve it. Around the mid-1835, she had a child. After the improvement on the formula she derived for some time she was able to publish the third edition of the "Luni-Solar and Horary Tables," which was made possible by the donations of the Admiralty, Trinity House, and the Honorable East India Company, to all of whom she dedicated the book too. She owed much of this success to the hydrographer Francis Beaufort, who helped push for the acceptance of her work by the Naval establishment. The increase in fortune from the bookselling allowed the Taylors to move to No 103 Minories, and this is where they set up a "navigational warehouse." This success meant Taylor was increasingly recognised as a credible mathematician and entrepreneur. For some years after, she continued to edit her book, later renamed to "Lunar-Solar and Horary Tables" selling a total of seven editions. The last print appeared in 1854. Also, she completed twelve editions of an "Epitome of Navigation," with the last edition appearing in 1859. George Taylor ended up taking up the publishing parts of the enterprise in order for Janet to devote time to raising the children and continuing her writing.
In 1843, Taylor decided to change her focus on compasses in iron ships. She worked specifically with the astronomer George Biddell Airy, who later would recommend her name to anyone who would be able to utilize her efforts. In 1845, she appointed William Reynolds to develop a nautical instrument factory in her name, resulting in instruments being entered in the Great Exhibition 1851 and the International Exhibition of 1862. A series of unfortunate events fell upon her, first starting with her husband George Taylor' death in 1853, and then both of her senior employees leaving her to start their businesses. From 1860, Taylor began to receive a Civil List Pension of £50 per year, and around this year her nautical academy changed its name to Mrs Janet Taylor and Co, meaning that it had turned into a company. There is record of her paying land tax for her company up until 1866 but by 1870 she became ill. During this time she was with her sister Joyce and her husband the Rev. Matthew Chester. On the 26th of January in 1870, Mrs. Janet Taylor died of bronchitis. On her death certificate, her occupation is stated as "Teacher of Navigation."
- Lunar Tables for Calculating Distances
- Luni-Solar and Horary Tables
- Principles of Navigation Simplified
- Epitome of Navigation
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