Belmond Mills Smaller

Old Mill on the Iowa River (click to enlarge) Belmond Historical Society

By The Metric Maven

In my single digit youth I often walked across the “old bridge” in my small town. One could see right off of the concrete bed of this truss type bridge over the Iowa River. I noticed that a small dam existed with an opening near the center of the river. People would often walk out on this dam, which had a height of only 1 to 1.5 meters or so, and fish. One day in the local library I saw a painting that showed an old mill had been on the river. I was quite surprised and asked if it had really been there. The librarian said it had, and was washed away during a flood.

Belmond historic 085

Old Bridge Over The Iowa River    (Belmond Historical Society)

It was a decade or so later that I learned photographs of the “old mill” existed. One of them is inset above. On the far right side of this photo is the location of the “new mill.” A local history1 offers little detail about the design of the “old mill.” Before the old mill, there was an original mill. A dam was constructed and:

The river provided the power for the first flour and sawmill built in 1855 or early 1856 by Dr. Cutler and Archer Dumond.” … “After only a few months’ use, this first mill constructed by the early settlers was washed away by flood waters in the spring of 1856.

In 1857, the next mill constructed was a steam mill. The following year, 1858, was so wet that the steam mill was surrounded by water that season. The machinery was sold and moved to Kansas. Apparently, rather than use the river for a source of power, an experimentation with steam took place.

The “old mill” in the photograph was constructed on the site of the “original mill” in 1858 by G.H. Armsbury. It was both a sawmill and gristmill. It is not stated if it was a water powered mill, but judging from the details of the transaction, it probably was. In 1863, George A. Thompson took charge of the gristmill. His relative Joseph Fulton became a part-owner of the mill, which, in 1870, was the only flour mill in Wright County. In the Spring of 1870 Fulton became entangled in the mill workings when he went to the basement to oil some of the parts. He was killed instantly. Assuming this is a mill that utilized a flat mill stone, they could revolve up to 125 RPM, with a considerable mass.

The mill dam was renovated numerous times before the “old mill” was finally retired. The “new mill” was constructed about 1901 and the “old mill” was:

….being torn down. The timbers are rotting away and it would soon be at the mercy of the first serious wind storm. In the days of long ago, it furnished flour to farmers as far away as Spirit Lake.

The last mill in Belmond Iowa was torn down in 1935, the location of the final millstone is a mystery. The bridge I traversed as a boy was the only structure left from this time period. It was replaced decades ago. I suspect the millstone was a flat affair that was common at this time. It is my understanding that some people actually collect old mill stones which have many unique cutting patterns rendered on their surface. Grain would be fed into the hole at the top. It would work its way down into the meeting line of the rotating upper stone and the static lower one. The milled grain then worked its way outward where it was collected.

I thought about this local history when I was re-reading The Ancient Engineers by L. Sprauge de Camp. The grinding of grain was of paramount importance to the creation of bread. This was a consistent staple: (page 243)

“…Throughout the ancient empires, bread was the principal food. To make it, wheat or barley grain had to be ground into flour. At first the grain was painfully pounded with a pestle in a mortar, as you can still see done in Central Africa.

At a later time, the grain was ground between two flat stones, one of which was pushed back and forth over the other. With such a mill, one person—usually a slave girl—could grind each day only enough grain to make bread for eight people. Hence, in a large household, several such women would have to spend their entire day at the weary task of pushing and pulling the upper millstone. The two ever-present sounds of ancient households were the clack of the loom and the grate of the hand mill.”

The implementation of water power to grind grain, is a perfect example of employing engineering to help keep a community fed, and reduce the horrible mind-numbing boredom of an essential all-day repetitive task.

All of the examples of millstones I had seen were a pair of stone cylinders with a flat interface between them. The small hand versions are called quern-stones. The large millstone examples I had seen using water power were always like this. One stone had patterns cut into it for the grain to be ground and then work its way out from the center where it could be collected by a pan at its edge.

I encountered a pair of surprises when L. Sprauge deCamp offered this drawing of a hand mill from ancient Pompeii:

Hourglass-Mill-AEThis is known as an hourglass mill and was used in Hellenistic and Roman times. I was quite surprised that it was possible to make stone conform to these shapes, but what really confused me were the dimensions. Throughout The Ancient Engineers, all the dimensions are in Ye Olde English. The book was published in 1960, so this is not surprising, but what on Earth were the units m/m? I knew that ca. meant “approximately,” or “about this dimension,” but m/m was strange. I hypothesized that it was millimeters—even though the entire complement of the book is in Olde English measures. The values 900 mm and 700 mm seemed to make approximate sense. What is wonderful about our modern world is that I can do a web search on hourglass mills and see photographs of the mills at Pompeii:

HourglassMillPompeiiThe dimensions in millimeters found on the drawing make sense, but the use of m/m for millimeters was unknown to me at that point. I consulted with Peter Goodyear, and he found examples of guns drills, and clocks that are still designated with m/m for millimeters! I have no idea where the designation m/m originated, but amazingly it is still in use.  Indeed here is a specification table from a Tawianese company that makes paper cutters:

Paper-Cutter-m-slash-mI’m pleased they used millimeters, but amazed and annoyed that m/m is used for mm. This is another example of an introduced usage from another era that continues to complicate our modern world in an unnecessary manner. It also demonstrates just how hard reform that would simplify our world is to achieve.

[1] History of Belmond, Iowa 1856-2006 Belmond Historical Society


The Metric Maven has published a new book titled The Dimensions of The Cosmos. It examines the basic quantities of the world from yocto to Yotta with a mixture of scientific anecdotes and may be purchased here.


Lost in Unit Space

Alpha-Centara-Centauri-CroppedBy The Metric Maven

Bulldog Edition

When I saw the initial episode of Lost in Space, one moment which captured my attention was when they showed the destination planet. I thought I recalled a sun and numerous planets, but the image to the left shows it was just a fuzzy circular smudge. When viewed from the mid-1960s, the world of 1997 still had desks with ashtrays and physical inboxes on their surface, but no computers.  It was also a time when the best images of the known planets in our solar system were but blotches of color with fuzzy details. When Voyager 1 took photos of Jupiter and revealed its swirling colors that resemble the marbling on the inside covers of antique books, it was astonishing. The rest of the planets followed during that “grand tour” era, all but Pluto. It would be reclassified as a Kuiper Belt object or at best a “dwarf planet” before it was imaged with a spacecraft. In 1978 James Christy noted a periodic elongation of Pluto and hypothesized that it had a moon. The images were fuzzy and lacking in detail, only a sort of bump could be seen. Until the New Horizons space probe produced crisp images in 2015, Pluto was only seen as ill-defined regions of light and dark brown areas.

I was quite enraptured when I saw this image on Gizmoto in the article: Incredible Photo Shows an Exoplanet Orbiting Around its Host Star I mistakenly thought it was the first planet ever imaged directly, but it is not. Bad Astronomer, and Bad Metric User, Phil Plait set me straight. Neil de Grasse Tyson may be your personal astrophysicist, but Phil appears to be the hardest working astrophysicist. He posts a prolific number of essays on his blog and they are quite interesting.

Six years back, on June 30 2010 (2010-06-30) Plait’s Bad Astronomy blog is titled: Another Direct Picture of a Planet Orbiting an Alien Star Confirmed! Exoplanet 1RXS 1609b was the first planet imaged with a ground-based telescope. The first exoplanet to be imaged, according to the Bad Astronomer, is 2M1207b shown below:


2M1207b and its star

Plait indicates:

It orbits the star at about 1.5 times the distance Pluto orbits from the Sun. The two are close by as these things go: just 70 parsecs (230 light years) from here.

I’m fine with a comparison to Pluto’s orbit, but it would have been nice if he used the metric system for the distance from us. In the case of the first star mentioned Plait offers:

..we know the planet 1RXS 1609b has about 8 times the mass of Jupiter, orbits the star 45 billion km (27 billion miles) from its star — 300 times the Earth-Sun distance …

Forty Five billion Kilometers? I’m sure that Phil Plait is of the view that Kilometers are a distance that is “everyday” and so saying there are a billion of them (using an Olde English “prefix”) is much more expressive to the public than 45 000 Gigameters. There seems to be no astronomer exception for AUs and parsecs for the public, so why is there for metric?

Rather than using astronomical argot like parsecs, AUs and light-years, let’s sort all of this out using the metric system and Naughtin’s Laws (as much as possible). Wikipedia does not assert that 2M1207b was the first exoplanet imaged, but we will assume it is. 2M1207b is currently thought to orbit at about 6000 Gigameters from its star. Pluto is at about 5914 Gm so exoplanet 2M1207b is at about the same distance out as Pluto. The star itself, 2M1207 is only around 1600 Petameters distant (a light-year is about 9.46 Pm). This star is very close to us. It makes sense we would first see an exoplanet around a nearby star rather than one that is farther away.

New Scientist TRAPPIST-1There have been many planets that have been indirectly inferred to be orbiting other stars. In August of 2016 New Scientist (pg 8) mentions the ultracool star TRAPPIST has three potentially habitable planets orbiting the same star. See upper graphic.

The three planets are surprisingly close to TRAPPIST-1 ranging from 2-3 Gigameters or so. Mercury orbits at 58 Gigameters from the Sun. If they orbited our Sun, these planets would be well inside the orbit of Mercury.


Table 1  — Click To Enlarge

The above table helps put the information into context using metric prefixes. The planets orbiting TRAPPIST-1 are all very close to their star. Because it is ultracool (in the temperature sense) the orbiting planets are potentially cool enough for life as we know it to exist. The first imaged exoplanets 2M1207b and 1RSX1609b orbit at a distance about equal to Pluto in the first case, and  about 7.5 times that distance in the second. When mapped onto our solar system, none of these new planets orbit within the same range as our planets.

The only exoplanet in the table with an estimated diameter, 2M1207b, (210 Mm)  has a diameter larger than Jupiter (140 Mm). It would make sense that a planet would have to be about this size to allow for measurement of its extent. Distances to these stars are expressed with Petameters, which means they are very close to us. The extent of our Galaxy is about 1000 Exameters or 1 000 000 Petameters, so TRAPPIST-1 (370 Pm), 2M1207 (1608 Pm) and 1RXS 1609 (4440 Pm) are close to us when compared with our galaxy’s dimensions.

Astronomers appear to be generators of unit proliferation. When you look up the diameter of 1RXS 1609 in Wikipedia, its radius is listed as 1.35 solar radii. The brown dwarf 2M1207 is about 0.25 solar radii, but its orbiting planet 2M1207b is given as 1.5 Jupiter radii. Astronomers have chosen to express measurements using metaphorical units in terms of arbitrarily chosen objects in our solar system. Why not use the metric system directly?—and then offer an example for context?  Mass is expressed in terms of Jupiter’s mass, but the temperature of the planet is given in kelvin. Why is the temperature not in terms of Jupiter’s temperature?—just to stay consistent. Do astronomers have equipment that measures and outputs  values in Jupiter masses and radii?—I kind of doubt it—I hope.

Lest you think I believe there has been no metric progress, it appears that at least Wikipedia is slowly changing its ways, albeit inconsistently. If you look at the orbital distance of Pluto it is first listed in AU (astronomical units) and in parenthesis next to it are the same values in Gigameters. Metric is still in parenthesis as “the alternative” but at least it is there, and not expressed in millions of Kilometers. I’m rather sure that at one time I never saw Gm values on astronomy pages in Wikipedia, and so this is a positive change. The Equatorial and Polar radius of Pluto and Jupiter are first given in Km and below each value is an equivalent Earth value, 11.209 Earths and 10.517 Earths in the case of Jupiter, and 0.18 Earths for Pluto. The volume and mass also have metric first and a suggested context second. I see this as a very acceptable way to designate these values. The mean density of Jupiter is in grams per cubic centimeter rather than 1.326 g/mL or 1326 g/L, so while it may have metric units in the expression it’s still more cgs than SI. Saturn is 0.687 g/ml or 687 g/L and because it is below one g/mL in the first case and below 1000 g/L in the second, an average chunk of Saturn would, in principal, float in water. Overall it seems that I’m seeing more use of the larger metric prefixes in Wikipedia and I definitely see that as a millimeter of progress in a country that has Yottameters to go.

Related essays:

Long Distance Voyager

The Expanding Universe


The Metric Maven has published a new book titled The Dimensions of The Cosmos. It examines the basic quantities of the world from yocto to Yotta with a mixture of scientific anecdotes and may be purchased here.