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An Overview of Joshua John Moore

Updated: 4 days ago


I believe the above sketch is Joshua John Moore as drawn by his close friend, Nicholas King, in 1795. The other images are of people who featured in Joshua's life once he moved to America.


Joshua John Moore was the father of Rev. Joshua Moore, the grandfather of Samuel Miller Moore, the great-grandfather of Mary Moore Watts, and the second great-grandfather of Walter Moore Watts Sr.


I consider Joshua John Moore to be the pièce de résistance of my genealogy project. I knew a few basic facts about him when I began, such as that he came from Cambridge, England, that he lived in Philadelphia at the end of the eighteenth century, and that he was a surveyor. And I knew that he married Elizabeth Massey in Philadelphia. That was about it. The Internet is an amazing thing, and I was able to find many dabs and dollops of information about him, which, when assembled, created a remarkable and magnificent whole. This will probably be my longest entry about any ancestor, even though I have condensed his story greatly.


The earliest I can find Joshua John Moore is in 1787, when he worked as an assistant to the fifth Astronomer Royal, Rev. Dr. Nevil Maskelyne. He was probably in his early twenties. As Astronomer Royal, it was Maskelyne’s job to observe the positions of the sun, moon, planets, and stars. Employing an assistant gave Maskelyne the ability to leave the Royal Observatory and spend time in London, where he was a fellow of the Royal Society, perhaps the oldest science society in existence.


Joshua John Moore was Maskelyne’s assistant from August of 1787 through January of 1788, a total of about eighteen weeks. Most of the assistants – they drudged one at a time -- only stayed a few months. The work was so tedious and precise that that’s probably all they could tolerate.


Maskelyne and his assistants worked at the Greenwich Royal Observatory, located on a hill about four miles from London.  The Observatory could not be left unattended, and so the assistants could rarely leave Greenwich. They were likewise discouraged from having friends visit them on site, and thus their social lives were quite constrained. However, if they were so inclined, the assistants could take advantage of Maskelyne’s vast personal library, which included novels in addition to scientific tomes and books about travel. Perhaps Joshua John took the opportunity to read about voyages to America and dreamt of a future there one day.


Determining longitude at sea was the holy grail of sailors in the Age of Exploration, necessary for successfully and safely navigating at sea.  Astronomer Royal Maskelyne developed a technique for determining longitude using the position of the moon and called the “lunar distance method.” Maskelyne believed that if lunar distances were calculated in advance, in the form of an almanac, sailors could use that information to navigate the seas.


Maskelyne’s lunar distance method relied on observations of the heavens made at the Royal Observatory. These would be put into tables showing the positions of the planets and other heavenly bodies and published in the form of an almanac, which could be purchased by navigators. Thus began the Nautical Almanac in 1767. As a testament to its international success, it is still being published in England to this very day.


In addition to his assistants at the observatory, Maskelyne oversaw what were referred to as “human computers,” the mathematically-gifted people who prepared the complicated tables for the Nautical Almanac. In 1787, after spending eighteen weeks at the Royal Observatory as Maskelyne’s assistant, Joshua John Moore was hired by Maskelyne to become a human computer for the Nautical Almanac. How remarkable it is that my fourth great-grandfather was one of the first human computers in history!


Thomas Browne is credited with first using the word “computer” in print in 1646. It was defined by the Oxford English Dictionary as meaning “One who computes; a calculator, reckoner; specially a person employed to make calculations in an observatory, in surveying, etc.” Of course a few centuries later the term had evolved to mean “an electronic device for storing and processing data, typically in binary form, according to instructions given to it in a variable program.” However, you can see that the origin of the word “computer” comes from the type of work that Joshua John Moore performed in the eighteenth century.


Maskelyne’s computers worked in pairs on their calculations, each using the same input and techniques, to produce the tables for the Nautical Almanac. To ensure quality control, a third person, known as a “comparer,” would compare the output of each computer to look for discrepancies.


Computers were free to live wherever they liked in England. They would simply mail their calculations to their comparer. Joshua John chose to live at the Angel Inn, a pub and inn in Cambridge, England. I believe his family may have come from a little town about five miles from Cambridge called Horningsea. Another man named Joshua John Moore – a generation younger than “my” Joshua John – migrated to Australia in the early 1800s and became a large landholder there. He hailed from Horningsea. Perhaps the two were cousins.


Joshua John computed for the Nautical Almanac about eight months of the year. He also worked part time as a surveyor, which required many of the same skills used in astronomy. After all, the practical application of astronomy involves measuring and mapping regions of the sky. Surveying is essentially the same thing carried out on terra firma.

Robert King, a Yorkshire surveyor of some note, was commissioned by an Act of Parliament to survey and map over 10,000 acres of land in England. In that capacity, he came to Cambridge in about 1789 and hired Joshua John to assist him, probably teaching him the basics of surveying. The two men came to know each other well and have great respect for one another. A year or so later, Robert’s son, Nicholas King – who had grown up in the profession of surveying and mapmaking -- came to Cambridge to finish a surveying job for his father. Joshua and Nicholas became fast friends.


By 1793, Joshua John and his fellow Nautical Almanac computers had become too efficient for their own good. Because some ships went on very long voyages, it was necessary for the computers to calculate tables several years out. The goal was to publish almanacs five years in advance. However, in 1793 , the computers put themselves temporarily out of business because their calculations were ten years out. The Board of Longitude, which paid the computers’ salaries, suspended the computations for a period of at least four years. After working for about six years as a computer for the Nautical Almanac, Joshua John lost his main source of livelihood. He was at loose ends.


Meanwhile, his friend, surveyor Nicholas King, had developed an antipathy for the British monarchy. Nicholas had read much about the new nation of America, and had great reverence for its quest for independence and wanted to be a part of “its grand experimental plan.” He decided to migrate to America, and Joshua John agreed to join him.


In the fall of 1793, Joshua John and Nicholas booked passage from London to New York City on the USS Hunter. It would set sail from London on October 20. To put the year 1793 into context, on February 25 of that year, George Washington held his first Cabinet meeting as President of the United States. In March, he was sworn in for his second term. The French Revolution was still raging and on October 16 — just four days before Joshua Moore set sail for America — Marie Antoinette was beheaded. On October 28, Eli Whitney applied for a patent on a gizmo known as the cotton gin. In 1793, the British admiralty began giving citrus juice to sailors to prevent scurvy, the Louvre was opened to the public as a museum, France adopted the metric system, and the United States Mint began producing its first coin — the half-penny. The U.S. Constitution was six years old.


Lucky for us, Nicholas King kept a journal of the trip and the first year or so the pair spent in America. Nicholas even gives us a clue about Joshua John’s family. He noted that Joshua John’s brother-in-law, a businessman named Mr. Edge, had seen the men off at the pier.


The journey by ship took about three months, and Joshua John and Nicholas landed in New York City in January of 1794. Someone – perhaps a fellow passenger -- arranged for them to meet a Dr. Samuel Lathrop Mitchill, a well-connected New Yorker, who might have suggestions for them about possible jobs. Dr. Mitchill was currently the chairman of the chemistry department at Columbia College. He would later become a U.S. Senator from New York. Dr. Mitchill suggested that surveying could be a very lucrative venture for the men. After all, in America, land was currency.  But the doctor gave the two young Englishmen something far more valuable than career advice. He presented them with a letter of introduction to his good friend and colleague, Dr. Benjamin Rush of Philadelphia, the nation’s capital.


In addition to practicing and teaching medicine at the University of Pennsylvania, Rush was a land speculator, and might be able to make use of some surveyors. He was also very well-connected in Philadelphia. Nicholas and Joshua could hardly have found a better advocate than Dr. Benjamin Rush, if only he would be willing to help them.


Benjamin Rush (1746-1813) was a Founding Father of the United States, a member of the Continental Congress and signer of the Declaration of Independence from Pennsylvania. His Founding Father bona fides are bolstered by the fact that Thomas Paine consulted Rush when he wrote “Common Sense” (Rush even selected the title), the pamphlet that so cogently spelled out the argument and rationale for the American Revolution. During the Revolution, he was Surgeon General of the Continental Army. Rush was a lifelong friend of Thomas Jefferson and John Adams, and famously helped them reconcile their friendship with each other after a political falling out in 1812.


Joshua and Nicholas eagerly took the stage to Philadelphia and soon found themselves in the home of Dr. Rush, who couldn’t have been more accommodating. Nicholas wrote the following about what transpired in his journal in February, 1794. It gave me chills to read about the encounter of my fourth great-grandfather with such a venerable man.


Republican Manners exemplified.


As an instance of the benefit society receives from Republicanism, in their Manners, shall relate an interview Mr. Moore and myself had with Dr. Rush: A gentleman in as much esteem as any one on this Continent. He lives in the greatest affluence, and is seemingly possessed of everything this world can afford, which is calculated to promote man[']s happiness.


To him, we had a letter of introduction from Dr. Mitchel [sic], Professor of Botany and Medicine in the College of Columbia New York. We waited on him one afternoon, and were introduced to him in an elegant drawing room where sat himself and two ladies. He received us in the most friendly manner. After we were seated the ladies withdrew with their work leaving us in conversation with the Doctor. Having explained our Views, and motives for leaving England, he gave us the greatest encouragement and that accompanied by pleasing instruction; promising to use all his interest for our service.


On leaving the room he took Mr. Moore by the hand expressing himself to us nearly thus. “Call often. Anything I can do for you, will be done with the greatest of pleasure. I consider it as a duty incumbent on me to render the same assistance to others, that my ancestors received when they fled from persecution and poverty.” Where is the Man, in Europe, who is familiar, a companion to the most dignified men in the nation that would have made such a confession to a stranger?


Men are here esteemed in proportion to their worth. The good man is the truly, nay, only Great man. Great attention is paid to the Recommendations Emigrants bring and the Company they keep.


They were very circumspect, in the article of recommending and without they have good assurance of the character of the person they recommend, will not do it.


I have been fortunate, all those to whom I have had letters interest themselves much for me. I hope I shall not deceive them; my heart tells me I shall not.



Dr. Rush didn’t have a job for them at that time, but he recommended them to Robert Morris, fellow signer of the Declaration of Independence, a land baron who had almost single-handedly financed the American Revolution. Morris was also the sitting U.S. Senator from Pennsylvania. To give an idea of the vastness of his properties, in 1791, Morris had purchased “essentially all of Western New York” for $333,333.33. He bought over 6 million acres in the rural south in addition to his large holdings in the District of Columbia. Nicholas and Joshua began working as surveyors and draftsmen for Morris’ North American Land Company.


Robert Morris had donated his home in Philadelphia to be the executive mansion for Presidents George Washington and John Adams before the capital moved to Washington, D.C. Nicholas and Joshua worked in offices next to George Washington’s house. One day in March, 1793, Nicholas King encountered President Washington and wrote this in his journal:


March 15th. Gen. Washington.


Although I sit in a room directly opposite the House of General Washington, I have never until this morning seen that valuable man.


As I was going to Mr. Morris’ office, I observed a Servant before the General’s door, holding two White Horses, and as I heard that one of these he generally rode out, was pleased with the thought of gratifying a wish long formed.


Many others, some of which seemed Strangers as myself were detained near the house by the same expectation. It was not long before he made his appearance. He mounted the Horse with the alertness of youth, and rode off as a private Gentleman; the servant following him at a short distance. As he passed along several of the gentlemen bowed to him, which he as politely returned.


He is a stout well built man and seems possessed of great health and activity, square faced, wears his own hair, which now is become Silvery, in a long slender tail. Had on Dark Coloured Cloathes [sic], Fantailed Hat with a Black Cockade. Rides with pistols in his Holsters, but the servant unarmed.


Joshua and Nicholas lived in Philadelphia for several years. In the course of his work for Robert Morris — who owned much of the land there — Nicholas King became part of the planning process for the city of Washington, D.C. In 1791, George Washington had selected it to be the new capital of the United States. He appointed three commissioners to get the city ready for its 1800 Grand Opening. The commissioners were so impressed with the work of Nicholas King, that in 1797 they appointed him to be the Surveyor of the City of Washington D.C. It was then that he and Joshua John parted ways, at least for a few years.


At about the same time, Robert Morris’ company, which had been highly leveraged, collapsed when loans from Holland didn’t come through due to the start of the Napoleonic Wars. Joshua John was out of a job. I’ll get back to that in a moment, but first I want to turn to Joshua John’s personal life.


Joshua John Moore is listed in the 1796 and 1797 Philadelphia City Directory, his occupation given as draftsman. He lived at 163 Vine Street.


But he didn’t live alone! On April 7, 1795, he had married Elizabeth Massey in the First Baptist Church of Philadelphia. When Joshua John and Nicholas first arrived in Philadelphia, just prior to their meeting Dr. Rush, a professor of literature named Dr. William Rogers escorted them around the campus of the newly formed University of Pennsylvania and introduced them to several of the professors. Joshua John and Nicholas developed an ongoing relationship with Dr. Rogers, who was also a Baptist minister affiliated with the First Baptist Church. He’s the minister who officiated at their wedding.

Dr. Rogers, a close friend of Thomas Paine’s, didn’t quite have the stature of a Founding Father, but as a crony of many of the Founding Fathers and as a brigade chaplain in the Continental Army, he might well have been considered a “Founding Uncle.”

Joshua and Eliza Massey had two children in quick succession, John Massey in December of 1795, and Elizabeth “Eliza” Edwards in 1797 or 1798. Dr. Rush seems to have come through with a job for Joshua as a surveyor around this time. He had bought thousands of acres of wilderness land in the Allegheny Mountains on spec, and had recently sold much of the property to the Welshman, Baptist minister Morgan John Rhys, who was developing a community known as Beula. Dr. Rogers also had a connection to Beula, and bought deeds to several lots there. Several hundred followers believed the town was going to make a difference in the lives of Native Americans and black slaves. Joshua John was hired to help lay out roads and the town. That’s where my third-great grandfather, Joshua Moore, was born in 1800.


In January of 1799, Joshua John applied for and was granted U.S. Citizenship. He had been in the country for the minimum requirement of five years. His petition, shown below, states that Joshua was “a native of Cambridgeshire in the Kingdom of England but now of Beula in the County of Somerset, State of Pennsylvania.”


A man named Thomas Shoemaker was his character witness. Thomas Shoemaker, a merchant, lived next door to Joshua John at 165 Vine Street in Philadelphia. He had married Ann Massey, the sister of Eliza Massey, just three weeks prior to Joshua John’s own wedding. Thus, the two men were brothers-in-law.

Beula fizzled out in the early 1800s. Joshua and a fellow surveyor from Beula named Thomas W. Jones collaborated to create a pocket-sized book of maps of the roads between New York, Philadelphia, and Washington, the same roads that later became I-95. It was an industrious and grueling undertaking. The book, titled The Traveller’s Directory: A Pocket Companion, was published in 1802. It was the very first Mapquest or Google Map, and it reads much like a road atlas combined with a Frommer’s travel guide.  

Joshua and Tom wrote colorful descriptions of the buildings, towns, geographical features, historical features, etc. encountered along the roads — giving mile-by-mile landmarks — and the maps are very detailed. It was a revolutionary book that gave people the freedom to travel on their own and not have to rely on stages lines. It holds a momentous place in the history of travel. The book was published by Matthew Carey, an Irish-born Philadelphia publisher whose career was jump-started by Benjamin Franklin and French General Lafayette. Unfortunately, somebody made a mistake in the printing and Joshua John’s initials were printed wrongly as “S.S. Moore.”


The e-book is available online and, amazingly, The Traveller’s Directory was reprinted in January, 2011 by the British Library as a historical print edition. It’s now possible to purchase a copy for about $15.00. It’s a shame that there was a printing error and Joshua’s initials are wrongly given as “S.S.” In a sense, Joshua lost that little piece of immortality.


Thomas Jefferson began his first term as President of the United States on March 4, 1801. With his administration, the nation’s capital shifted from Philadelphia to Washington City, as it was known, which Nicholas King was already helping to create and beautify.


Joshua John was on the road that year, but after his book was published in 1802, he settled down in Washington City. His daughter, Mary, was born there on September 15, 1802, so his family had to have been there by that date. He began working in the department of the Secretary of the Treasurer in the Jefferson Administration. One source puts him there in 1801, but I don’t know how he could have been mapping roads and working in Washington at the same time. Perhaps he was doing double duty.


Joshua became a clerk for the Public Land Survey System (PLSS), which had been proposed by Thomas Jefferson shortly after America was founded. The Continental Congress was deeply in debt with no power to tax. Jefferson thought that the federal government could sell land in the Western Territories to pay off the debt incurred by the Revolutionary War. The thirteen original colonies donated their western lands to be developed into new states. Those lands became the Northwest Territory, Kentucky, Tennessee, Alabama, and Mississippi. The PLSS was established to determine a process by which the land in the western frontier could be methodically divided into saleable parts.


By the time Joshua John came on board, the PLSS came under the auspices of the Treasury Department. His immediate superior was Treasury Secretary Albert Gallatin, a multi-talented Swiss-American. The founder of what is now New York University 1838, he was an “ethnologist, linguist, politician, diplomat, and congressman, and the longest-serving United States Secretary of the Treasury.” His tenure was from May 14, 1801 to February 8, 1814. We’ll run into Albert Gallatin again in another family line.

Surveying and mapping the Western lands was the perfect fit for Joshua John Moore. In his capacity of clerk with the Public Land Survey System, Joshua soon found himself teaming up again with his good friend Nicholas King.


In 1801, Secretary of the Treasury Albert Gallatin commissioned Nicholas King, the Washington City Surveyor, to produce a map of the western lands for the Public Land Survey System, the very agency in which Joshua John was employed as a clerk. Nicholas and Joshua John worked together on this project, which involved compiling a map of the “lands of the United States Northwest of the River Ohio.”


In 1803, Gallatin hired Nicholas for a similar task, “to project a blank map . . . which will give us the whole course of the Mississippi and the whole coast of the Pacific Ocean . . .” 


The resulting map “became the base for a composite map by English and French cartographers and explorers, which Clark and Lewis studied in detail prior to their departure from St. Louis, May 14, 1804.” In other words, Nicholas (and possibly Joshua John!) prepared the map used in the Lewis & Clark expedition!

Nicholas didn’t travel out West himself, but did what he and Joshua had done in their earlier undertaking: he studied maps made by a variety of cartographers and explorers over the years. He (and maybe Joshua John!) tried to determine what was accurate and what wasn’t, and developed a composite of all the maps.


Right now I can’t prove that Joshua John worked with Nicholas in creating this blank map. The fact that they collaborated on the first and very similar project under Gallatin suggests that he very well might have. The men clearly worked well together as a team. The thing is, I only found out somewhat accidentally that Joshua John was involved in the first project. The name “Moore” was joined with King’s in one reference to it, but no first name was given. I just happen to know it’s got to be Joshua John! Because Joshua was “merely” a clerk, his name would not have been formally attached to the project. Perhaps there are records somewhere that would reveal the answer.


As early as 1801, Nicholas King saw a need for a prime meridian in the United States. The maps that he and Joshua were analyzing had discrepancies because each cartographer had used his own reference points.  The purpose of a prime meridian is to have a common reference point from which everything else is measured, standardizing the process of map making. Nicholas suggested that a point in Washington City should be designated as the National Meridian. In 1804, President Jefferson Agreed. He considered an American prime meridian to be a prerequisite to the Lewis & Clark and other expeditions to explore American territory.


Fellow surveyor Isaac Briggs was appointed to determine the prime meridian of the United States. He asked Nicholas to assist him. A monograph about Nicholas King says:

Having acquired a knowledge of astronomy form his long-time companion, Joshua John Moore, King was well qualified to assist in such an important undertaking.


And so an imaginary line was run down Pennsylvania Avenue and through the center of the White House. It would be ground zero for the purpose of determining longitude and latitude in the United States. (The line for the Washington Meridian was changed two times in the next few decades, but I’m not going to get into that here.)


But it seems that the Washington prime meridian was determined more by patriotism than by science, and was not destined to last. Other countries, like America, designated their own ethnocentric prime meridians, which was fine when only mapping their own countries, but not very practical in a more global sense. Scientific independence was not a very rational goal. By the mid-nineteenth century, America and the world recognized the need for a universally recognized point of reference.


In 1884, U.S. President Chester Arthur convened the International Meridian Conference in Washington, and delegates from 41 countries attended. Their task was to come up with one prime meridian that everybody could agree to upon. Because Britain had first solved the problem of determining longitude for ocean navigation, and the long history of Nevil Maskelyne’s Nautical Almanac, locating the prime meridian at the Royal Observatory at Greenwich was a foregone conclusion. Of course Joshua had left a small imprint on that decision as well.


In the early 1800s, when men were setting out to explore and map the western territory of the United States, scientists of the day tried to figure out a “clockless” way to calculate longitude while traveling on land. Normally longitude was measured by comparing one’s local time at noon with a clock set to Greenwich time, but it was felt that a chronometer wouldn’t be reliable for an extended stay in rugged conditions. Joshua John Moore was in the thick of this discussion.


In 1805, President Jefferson wrote to seven experts in astronomy, surveying, and mapmaking to ask for their opinions on the matter. Joshua exchanged letters with Jefferson, and suggested his own method for calculating longitude without using a chronometer. In two letters (one to a mathematician/astronomer and one to an explorer), Jefferson made references to the “Moore Method of Longitude.” In 1807, Joshua John was again one of seven surveyors and astronomers who collaborated with President Jefferson on a project involving surveying the coastline of the United States.


As far as his social and civic life went, Joshua John was active in a fraternal organization called the Sons of St. Tammany of the City of Washington. In 1808, he was elected to the board of directors of the Washington Academy, the classical school that his son, Joshua, attended. The membership rolls of both organizations read like a Who’s Who of Washington. 



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