Empirical Earth · a primary source, read in full

The Gleason map — what the patent actually says.

Alexander Gleason’s New Standard Map of the World (1892) is the single most reproduced image in flat-Earth circulation. It is sold as a poster, printed on shirts, and offered as evidence that a nineteenth-century engineer patented a flat Earth and that the patent office agreed with him.

The patent exists. It is US 497,917, and it is one page of text anyone can read in about four minutes. Almost nobody does.

What this page is. Not an argument about Gleason’s beliefs — he was a flat-Earther, he wrote a book saying so, and there is nothing to expose there. Nor is it new research: the patent has been quoted for years, and the passage everyone quotes is quoted here too. It is a reading of the document as a patent rather than as prose — what the claim legally covers, who ended up owning it, the class the office filed it under, and what the patents citing it turned out to be. Those four things decide what the document is, and they are usually skipped.
On this page
  1. What the patent actually claims
  2. Gleason’s own description of his map
  3. Who owned the patent
  4. How the patent office filed it
  5. What the map calls itself
  6. Did Gleason draw it?
  7. Lake Erie, and the arithmetic he ran
  8. The question he got right
  9. The man, and the book
  10. What the projection is
  11. What the map gets right
  12. Where it fails, and by how much
  13. What would settle it

01What the patent actually claims

A patent is not a general endorsement. It grants a monopoly on one specific thing, and that thing is set out in a section headed “I claim as my invention.” Everything outside that section is description. Only the claim is the property.

Gleason’s claim runs to a single sentence. Reduced to its parts, it covers:

1a circular time dial encompassing the circular map 2a graduated disk indicating longitude and sun time on any meridian 3two indicating arms loosely pivoted at the center 4numerals marking degrees of longitude along those arms 5a pivoted joint whose friction holds the arms wherever you set them
That is the whole claim. A dial, two brass arms, and a joint stiff enough to stop them flopping. The shape of the Earth is not claimed, not mentioned, and not at issue. The map is the surface the device sits on, in the way a slide rule’s claim covers the cursor and the scales rather than the arithmetic.

The document is titled TIME-CHART. Not a map, not a model of the world. Gleason opens by saying his invention concerns mechanical devices and geographical illustrations to be used on a flat circular map — a phrase that puts the map underneath the invention rather than in it.

02Gleason’s own description of his map

Two passages near the end of the specification decide the matter, and Gleason wrote both.

He tells the examiner his map retains all latitudes and longitudes agreeing with other recognized authors, and describes the continents and cities as laid out with coordinates corresponding to those of all other first-class geographical globe maps. His own document uses the word globe, approvingly, as the standard his sheet agrees with.

And then the sentence that is quoted often enough, and read carelessly enough, that its force gets lost:

“The extorsion of the map from that of a globe consists, mainly, in the straightening out of the meridian lines…” Gleason, in the patent specification, describing how the map was made.
“Extorsion” is a nineteenth-century word for distortion — a twisting out of true. Gleason is stating plainly that his map is a globe distorted by straightening the meridians. He is describing a projection, and he names what it was projected from.

This passage is well known and widely reproduced, including by flat-Earth sites, which usually gloss it as a slip of vocabulary. It is not a slip. It is a working description of method, in a document where Gleason had every reason to be exact: a patent specification is a legal instrument, and vagueness in one gets it rejected. A map cited as proof the Earth is not a globe carries, in its own patent, a plain statement that it is a flattened globe — written by the man selling it.

03Who owned the patent

The heading of the specification names the inventor and then, in the same breath, the owner.

inventorAlexander Gleason, of Buffalo, county of Erie, State of New York assignor tothe Buffalo Electrotype and Engraving Company, of the same place filed15 August 1892, Serial No. 443,074 granted23 May 1893 witnessesJames Sangster, Jennie M. Caldwell

Gleason assigned the patent to a printing firm. An electrotype and engraving company made printing plates; that was the business. The rights went to the people who would manufacture and sell the sheet.

This reframes the object. The map that circulates as a suppressed truth was a commercial product, patented by its designer and assigned to a Buffalo print shop to be produced and sold. That is not a criticism — it is an ordinary and honest way to bring something to market. But it is not the story usually told about it, and the detail sits in the first three lines of the document.

04How the patent office filed it

Patent databases carry the classification the document was given. Gleason’s sits at:

G09B 29/00 — Maps; Plans; Charts; Diagrams
G09B 29/14 — Local time charts The category the document lives in, then and now.

Not a category about the shape of the Earth. There is no such category, because patents are not granted for cosmological claims. They are granted for devices and processes.

The four later patents that cite Gleason show what it was understood to be. All four are navigation and teaching instruments: an educational apparatus in 1950, and three planispheres and sight-reduction finders from the Eisenhauer Manufacturing Company between 1975 and 1978. The patent’s descendants are navigational calculators.

It was not novel in kind either. The comparable documents include a geographical clock patented in 1877 and another in 1903. Circular world charts with rotating time arms were a recognized class of instrument before Gleason and after him.

05What the map calls itself

The sheet carries a long title, and almost every reproduction crops it. In full it reads:

Gleason’s New Standard Map of the World: on the Projection of J. S. Christopher, Modern College, Blackheath, England; Scientifically and Practically Correct; As ‘It Is’.

Longitude and Time Calculator; Patent Allowed, November 15, 1892. Applications made in: England, Canada, France, Denmark, Sweden, Germany, Austria. Published by the Buffalo Electrotype and Engraving Co., Buffalo, N.Y., U.S.A. The map’s own title block.
Two things sit in that title, printed on the map itself.

Gleason credits the map to someone else. He never claimed to have devised the way the world is laid out on his sheet, and the title says so on its face. What he added was the time dial and the two arms — the part he patented, and, as the next section shows, the part that was not there when he first printed this map in 1885.

And it calls itself a Longitude and Time Calculator. Not a map of a flat Earth. The description that matches the patent is printed in the title, by the publisher, on the object.

The remaining lines are commercial: a patent allowed in November 1892, applications lodged in seven other countries, and the publisher named. The November 1892 date and the May 1893 grant date are not in conflict — allowance is the examiner’s decision that a patent will issue, and issue comes months later once the fee is paid. The map was printed in the gap between the two, which is why it advertises an allowance rather than a number. An inventor filing in England, Canada, France, Denmark, Sweden, Germany and Austria is protecting a product, and the ambition tells you what he thought he had.

06Did Gleason draw it?

No. He republished someone else’s map and added the timepieces.

The evidence is a sheet Gleason printed seven years before the famous one, and it settles the question on its own.

The New Map of the World on the Projection of J. Steer Christopher, Morden College, Blackheath … Without Any Antipodes Gleason, 1885. Closely resembles the 1892 map, and has no indicator arms.
The map existed before the apparatus did. Gleason issued it in 1885 as a plain sheet, reissued it in 1892 with a time dial and two brass arms laid over it, and patented the arms. The continents, the projection, the layout — those came first and came from elsewhere. What he added in 1892 is exactly what the patent claims.

The antiquarian dealer Michael Buehler, who has handled two of the four known copies, traces the line: Joseph Steer Christopher published a flat-Earth map on a north polar azimuthal projection at some point in the 1880s, and Gleason obtained it and reprinted it. Buehler is careful about the limit of the evidence, and so is this page: references to Christopher’s map survive, but no image of it has been found. The chain runs backward from Gleason’s own 1885 edition by reference, not by laying two sheets side by side.

Where this could be wrong. The 1885 sheet is itself very rare — Buehler reports finding only reproductions of it. If someone produces evidence that the 1885 map was Gleason’s original composition and that the Christopher attribution was decoration, then the answer to this section changes from no to partly. What would not change is the patent, which claims the arms and the dial and nothing else, and which is the primary document this page is built on.

The 1885 title is more accurate than the 1892 one

1885 sheet1892 sheet
the institutionMorden College — correct“Modern College” — wrong
the nameJ. Steer Christopher“J. S. Christopher”
indicator armsnoneadded, and patented

The misspelling everyone notices was not in Gleason’s first printing. He had it right in 1885 and lost it by 1892.

And the back of the sheet gives the game away in one sentence. The printed “Descriptive Key” on the verso closes with a line that no confident flat-Earther would write: the demonstration has reference to either consideration — the earth a globe or a plane, take your choice.

That is the map offering itself as agnostic on the very question it is now sold to settle. It sits on the object, in print, and it is the same posture as the patent: a commercial sheet that declines to commit, sold by a man whose four-hundred-page book commits on every page.

And who was Christopher

Not a cartographer. Born 1805 in Dartmouth, Devon; a merchant at the East India Chambers who declared bankruptcy in 1844; a railway investment scheme the following year; soliciting investors for a “Natal Company” in 1850; some years in Natal, and a book about it published in London the same year. From 1875 he was resident at Morden College — not a teaching institution at all, but an almshouse founded by Sir John Morden, a Levant and East India merchant, for traders who had lost their fortunes. He was still there at the end of 1894.

So the attribution line has been read backwards. “On the projection of J. S. Christopher, Modern College” gets quoted as though it named an authority and an institution standing behind the map’s geometry. It named a bankrupt merchant living in a charitable home, and the projection was public property — centuries old, and used on printed maps by 1713. Christopher no more invented it than Gleason did.

07Lake Erie, and the arithmetic he ran

The 1893 edition of Gleason’s book carries his own field tests. The contents page lists tests on Lake Erie, the Erie Canal and other places, and the historian Christine Garwood records him observing from the roof of Buffalo City Hall.

In the Lake Erie account he gives two distances from a single observation point, and states that the land should have been about four hundred feet below his line of sight.

22 milesto the Welland Canal on the Canadian shore 27½ milesto the mouth of the Niagara River ~400 ftthe drop he calculated, and did not see

His figure is recoverable. It is the eight-inch rule applied to the total distance:

8 × 22² inches = 323 ft   ·   8 × 27.5² inches = 504 ft His 400 sits between them. That is the calculation he ran.
But that formula answers a different question. It gives the drop of the surface below a flat line running out from the eye — a real quantity, and not the one that blocks a view. What blocks a view is the bulge between observer and target, and the input for that is the distance past your own horizon. A formula with no eye-height term in it cannot be describing what hides a shoreline.

Run it properly, subtracting his own horizon first:

Eye heightHorizonHidden at 22 miAt 27½ mi
10 ft, standing at the water4.2 mi182 ft311 ft
50 ft9.4 mi91 ft188 ft
100 ft13.2 mi44 ft116 ft
200 ft18.7 mi6 ft44 ft
His actual eye height is not recorded, and this page does not guess at it. Garwood says he observed from the roof of Buffalo City Hall; she does not give a height, and roof is not the same as tower. The table above is there to show the shape of the relationship, not to reconstruct his day.

And the argument does not need it. Whatever height he stood at, his figure of about four hundred feet came from a formula with no eye-height term in it. A calculation that gives the same answer whether you are lying on the beach or standing on a tower cannot be describing what hides a shoreline. That is true before anyone establishes where he was.
And the framework is inherited. The contents page of the same book lists the Suez Canal as a hundred level miles, and a book of British standing orders — Rowbotham’s arguments, item for item, carried over from Zetetic Astronomy. The tests on Lake Erie are Gleason’s own. The reasoning he brought to them was not.

08The question he got right

A Kansas newspaper in February 1897, surveying flat-Earth advocates, records something about Gleason that is usually left out. He advertised in a New York paper for sea captains who had sailed from the West African coast around Cape Horn, wanting to establish whether that distance was greater than a sphere allows.

That is the right experiment. Southern distances are exactly where the azimuthal equidistant projection fails, and Gleason understood it well enough in the 1890s to go looking for data. He wrote to the only people who had it, which is what a serious investigator does when the measurement he needs is out at sea.

The answer he could not get then is a timetable now. Qantas QF27 flies Sydney to Santiago in about twelve and a half hours, directly across the southern Pacific — a route that on his own sheet runs around the outer rim and is one of the longest journeys on Earth.

The newspaper adds that the information satisfied him and convinced few others. Reading it at a distance of a century and a bit, the honest observation is that he asked the question the map could not survive, and the instruments of his day could not answer it cleanly. Ours can.

09The man, and the book

born28 November 1827, New York died13 March 1909, aged 81, Darien Town, Genesee County, New York tradenever a civil engineer, despite what most sources repeat. The Buffalo City Directory lists him as solicitor (1882–83), machinist (1889), engraver (1893) and patternmaker (1898), across at least six addresses. churchhelped establish a Seventh-day Adventist church in Buffalo in 1889 — the historian Robert Schadewald called him the most important Adventist flat-Earther in the United States address1201 Niagara Street, Buffalo, as printed by the Buffalo Commercial in 1890

His own city treated him with amused tolerance. A short Buffalo Commercial item in November 1890 remarks that nothing seems impossible to a Buffalonian and suggests that once Mr. Gleason has demonstrated his theory he will take possession of the earth in the name of his native city.

Three years later the same paper reviewed the book seriously enough to say that if the diagrams and measurements were correct, there were hard nuts there for scientists to crack — and named the publisher: the Buffalo Electrotype and Engraving Company.

He published Is the Bible from Heaven? Is the Earth a Globe? in 1890 — a short volume of about ninety-five pages, half scriptural and half against the globe. After the map appeared he issued a much enlarged second edition in 1893, running past four hundred pages and adding accounts of his own experiments along the Erie Canal.

So the honest framing is not that Gleason was secretly a globe man. He was not. It is that a man who spent four hundred pages arguing against the globe, when describing his own map to a patent examiner, wrote that it was extorted from that of a globe and that its coordinates agreed with first-class globe maps. He was precise in the one document where precision was required of him.
Which closes a circle worth noticing. The same Buffalo firm took the assignment of the patent, printed the map, and published the four-hundred-page book. The map and the book were one commercial package from one printer, and the patent was the part of it that could be owned.
Four copies are known. Three sit in institutions — the Leventhal Map Center at the Boston Public Library, the National Geographic Society, and Yale. The map that fills the internet is a reproduction of the Leventhal copy. The original is a genuine rarity; the poster is everywhere.

10What the projection is

Strip the brass arms away and what remains is an azimuthal equidistant projection centered on the North Pole — a standard way of flattening a sphere, still in use today.

It preserves two things measured from the center point: every distance and every bearing from that center is correct. Everything else is sacrificed to achieve it. The further you move from the center, the more the map stretches, and it stretches without limit.

The projection is honest and useful. Radio operators use it to aim antennas. Seismologists use it to plot wave arrivals. The United Nations emblem is one. Gleason did not invent it and never claimed to; his contribution was the timekeeping apparatus laid over it. Every criticism below is of the reading imposed on the map, not of the map.

A good deal, and it should be said plainly.

the northShapes and distances across the northern hemisphere are close to correct, because that is where the projection is accurate. coordinatesEvery latitude and longitude on the sheet matches the globe. Gleason says so in the patent, and it is true. the deviceThe arms genuinely work. Set one to your meridian and one to another, and the difference is right, because time zones are 15° of longitude per hour on any projection that preserves longitude. the purposeThe specification is written around a child reading the time in London off a dial. That is a real and decent aim.

12Where it fails, and by how much

The failure is not vague. It is measurable in hours, on scheduled flights, this week.

Because the projection stretches everything southward, any two southern cities are drawn far further apart than they are. The map has no way to show the Southern Hemisphere as anything but an ever-widening rim.

RouteGreat circleVia the northMeasured
Sydney → Santiago7,047 mi direct13,078 mi via Los Angeles1.95× the time

A globe predicts the direct route is 1.86 times shorter. Measured block times give 1.95. The Gleason map predicts no advantage at all — on that sheet the direct southern route is not shorter, it is longer.

The test is a timetable. Qantas QF27 flies Sydney to Santiago in about twelve and a half hours, directly across the southern Pacific. On the Gleason map that path runs around the outer rim and is one of the longest journeys on Earth. The aircraft does not know that, and neither does the fuel load.

The same failure appears on every southern pairing — Johannesburg to Perth, Cape Town to Buenos Aires, Santiago to Johannesburg. Each is flown directly, each takes the time a sphere predicts, and each is drawn on Gleason’s sheet as far longer than it is.

13What would settle it

Read the patent. It is one page, it is free, and it is at patents.google.com under US 497,917. Everything on this page is in it. Nothing here requires trusting this site.

And if the map is to be used as evidence, three questions follow from the document itself:

1Which sentence of the claim concerns the shape of the Earth? The claim is set out above in full; the answer is none of them. 2What did Gleason mean by the extorsion of the map from that of a globe? He is describing his own method. 3How long does QF27 take? The map predicts one answer and the timetable gives another.

Related in the main reference

Maps and projections Circumnavigation The southern sky Polar flights The aviation page Every formula, decoded
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