Maps from 1590 through 1776

The map in progress
A year ago at this time, I wrote about a map I was making for Northumberland county, Virginia. The map has been sitting there, idle, ever since while I’ve been off working. If I didn’t have to work, I sure would like to devote more time to this incredibly interesting subject of cartography and map making.

Anyway, I have recently returned to the map. The problem in completing this map has been, of course, the creative part.

It dawned on me last week that the illustration for the bottom of the map, which, if faithful to my father’s idea before he died in 2005, would have been to place a series of historic homes with a description of each. However, he intended to have a series of the same map which progressed over the years from 1600 through the present time. I, on the other hand, am going to make just one version. So the problem becomes one of representing 400 years of history in one map. I finally decided that a good solution might be to place a series of maps across the bottom, advancing through time, and with some significance to the choice of each map.

Ah, pretty good idea. So here is the bottom of the map:

Four very important maps

These are very important maps, as they served as the prototype for many copies until superceded by the next prototype. The first map is by John White in 1590. The second is by John Smith in 1612, The third is by Augustine Herrman in 1673, and the forth is by Josha Fry and Peter Jefferson in 1753. There have been hundreds of maps published for the Chesapeake Bay region, but it is these four maps which were the foundation for all other maps. As for the main large map, I have not decided on a time, but am leaning towards the early 1900’s. I’d like to capture the time when the local Menhaden fleets where emerging, and sailing ships could still be seen on the water.

If you zoom in to these maps, you will see very many interesting details. Here is an example from the Fry and Jefferson map of 1753:


One last interesting technical point I discovered. I scanned the maps in at 300DPI, which is very acceptable for resolution. The funny thing about Adobe Illustrator is that, when I brought them in for trimming, and then saved them, they got saved at 72 DPI even though I specified “maximum” resolution in my “Save For Web…” dialog box. When I brought the images back in, they were fuzzy, of course, at 72 DPI.

I could not find anything that would let me increase this save DPI setting.

No good at all. It took a while, but the solution turned out to be this. When the original 300DPI image is brought in to Illustrator, immediately scale it by 500% before working on it. Then, when you do your cropping and so on, and then save it at the hardcoded 72DPI value, it goes out to the file as a very large image at 72DPI. When you bring it back it later, to include it in any artwork, if you then scale it back down by 20%, it goes back to 300DPI and returns to its original sharp resolution.

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Size of a gore for a 30-inch globe

Printing the gore, actual size = 47.123890 inches

I printed out a gore last night. Just the vector outline for the continents, so it is very basic in order to get an idea of actual size. And so, just what is the actual size of a gore?

The circumference of a 30-inch globe is 94.24777960769379 inches.

The length of the gore is c/2, which is 47.123890 inches.

The width of a gore spanning 15 degrees longitude is c/(360/15) = 3.926991. The width of a gore spanning 30 degrees longitude is c/(360/30) = 7.853982.

Now, the real question is, have I got enough significant digits? If we take a 15-degree gore whose width has been calculated as 3.926991, and multiply by (360/15), the answer is 94.2477840.

The original circumference was 94.24777960769379, so if we place the 15-degree gores side-by-side at the equator, it looks like we will have an accumulated difference of 94.24777960769379-94.2477840 = -0.00000439230621 inches. Since this is a negative number, we will have a very small overlap.

Hmmm, I wonder if that’s too much of an overlap? I’ll have to get my micrometer and see it looks like in real-life. Standby for further details.

Just outlines, no gradients or artwork yet.
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Just discovered the Bellerby Globes

A massive Churchill globe is complete

How could I miss this one? I must be pre-occupied with all the daily things at work. Well, you probably know what I mean.

I bought Simon Garfield’s book titled “On the Map”, which had some pretty good reviews as well as a great write-up in the Wall Street Journal. The Journal article came out about 6 months ago, but I’ve been waiting to place my Amazon order until I could accumulate a list of titles to purchase. When the book arrived, the first chapter I read, naturally was one titled “How to Make a Very Big Globe”.

It was pretty amazing to discover the work by Peter Bellerby. It turns out he had an idea to make his own globe about the same time as I, in 2008. The big difference, of course, is that he actually did it, and turned his project into a very successful company. Here is his web site, and I’m sure you will agree that the work is very nice:

More google searches turned up articles, youtube videos, and even a 3-day-old article at

I like these globes. Who wouldn’t? The reason I like them is not so much for the size or manufacturing process, but because they are hand-painted. This give the effect of age and unevenness without being old or worn out. They look original and hand-made, which they are. I suspect you could get the same effect with Adobe Photoshop, but I also suspect you wouldn’t be able to convey the transparency and color-stained effect in an authentic manner.

Since the globes are all hand painted, I would guess that the gores are fairly simple. Line vectors for the outlines, and text, along with a shoreline gradient. As I study the gores in the photos, I do see that there is a purposeful effort to avoid having text cross from one gore to the next unless the text is very close to the equator. This definitely solves a problem I’ve been thinking about, where the text must curve correctly at high latitudes when crossing across gores. Bellerby appears to have solved this problem by avoiding it altogether. I think this is probably a good idea.

So how much would it cost for his big 50-inch Churchill globe? Well, this particular globe will set you back US$86,427. Wow!! That’s more than a Mercedes.

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How heavy is a 30-inch globe?

I’d like a hollow plaster globe. Not a solid one, which would weigh 433 pounds, but a hollow one.

So how thick should we make the plaster? Initially, I’d guess about an inch thick as a minimum, with some internal reinforcement possibly, to prevent cave-in’s. So, just how heavy would this globe be? Let’s work out the weight…

If we want a 1-inch thick layer of plaster, the volume would be equal to a volume of a 30-inch sphere minus the volume of a 28-inch sphere. The volume for a sphere is calculated as V=(4/3) * pi * r3. Therefore, if a 30-inch sphere is 14137.166943 cubic inches and a 28-inch sphere is 11494.0403234 cubic inches, then the volume of a 1-inch thick layer of plaster would be 2643.1266196 cubic inches (14137.166943 – 11494.0403234 = 2643.1266196).

The density of plaster is equal to 0.490753134528 ounces per cubic inches, and the formula for weight is w=p*v. Given p and v, we can calculate the weight of the globe as 81.07 pounds.

A little heavy, but workable with a strong base.

How about some other thicknesses? Using the same formulas, we can work out some other weights for a 30-inch globe based on the thickness of the plaster:


Thickness (inches) Volume (cubic inches) Weight (pounds)
0.5 14137.166943 – 12770.0505397 = 1367.1164033 41.93
1.0 14137.166943 – 11494.0403234 = 2643.1266196 81.07
1.5 14137.166943 – 10305.9947014 = 3831.1722416 117.51
2.0 14137.166943 – 9202.77208112 = 4934.3948618 151.35

I think that a 1-inch layer of plaster is just about right.

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