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Volume X, No. 2, Winter 1982 |
COMPASS AND TRANSIT
THE DEVELOPMENT OF SURVEYING EQUIPMENT
by Deidra Morgan
Photography by James Heck, Cherie Burns and Deidra Morgan
One afternoon as I was going through some books in my uncle's attic, I came across a surveying manual published by W. & L. E. Gurley called American Engineers' and Surveyors' Instruments, dated August, 1910. I felt like a little kid finding a new toy. I then wondered if this was the way Robert Elgin and Dave Krehbiel felt when they discovered in an old barn somewhere a surveyor's notebook, some old compass or transit or an old piece of surveying equipment like a chain or a tripod.
Robert Elgin, engineer and surveyor for R. L. Elgin & Associates, said he first became interested in surveying equipment for its historical value and because he was interested in antiques and historical items. He bought his first old compass in 1933 when he started taking surveying courses, but didn't actually start collecting until about twenty-five years ago when a friend gave him one. That was all he needed to get him started.
Dave Krehbiel, an engineer and surveyor for Krehbiel Surveying, Inc., has actively looked for surveying equipment to enhance his collection. "About four or five years ago, I wanted to be able to show people that came into our office a compass and a chain," Dave said. "So I advertised in the Rural Electric Missourian. The first reply I got was for a chain and a small compass. The next reply, from the same ad, was a cir-cumferentor. In looking at the circum-ferentor, I found that I couldn't find any other that had been made in the United States. I thought, now this is real interesting-made right here in Missouri.
"The lady I bought the first chain from lived in south central Missouri. I went down there one
Sunday afternoon,
back a long dusty road and met the woman who was in her seventies. I spent three or four hours
with her and was just absolutely fascinated. She said when she was twelve years old, her dad was
a timber man and surveyed timber acreage. She would follow him along with a chain. She knew it
had to be pretty old, because they quit making chains somewhere around the turn of the century.
"The people that I met while looking for equipment and instruments have been fantastic. I found that the advertisement did do it in Missouri, so I started advertising in Illinois. Then from Illinois to Indiana. Also, Pennsylvania has been a good state for me. Then I started in Arkansas, and worked the southwest and the northwest. I've advertised in most of the United States.
"My objective in doing this was to let people be knowledgeable of the situation, to know about these instruments and their importance."
Finding the equipment is only the first step. Most of these instruments and equipment have to be restored. There is a great deal of care that goes into a collection of these valuable instruments. Dana Krehbiel, Dave's wife, does most of the cleaning and polishing. "People don't know what they have in these old instruments or what they are for," said Dana. "Usually the first place they put them is in the barn. One person said that a jacob staff was just an old pole that grandpa had laying around.
"People who try to do something with them will put a lot of lacquer on them.
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This doesn't help any." The best way to restore them is just to clean the brass instrument with a brass cleaner, polish it and buff it with a buffing wheel. There really isn't anything you can do to clean the wooden instruments.
As the care of these instruments is important today to preserve the history of surveying, the care of the instruments was important in early days. In the field the early surveyor usually kept his instruments in leather cases that he could attach to a back pack.
When the United States was being settled back in the late 1600s to early 1700s, the people who settled here were poor. They didn't bring brass surveying equipment to America from England, mainly because they couldn't afford to. The surveyor couldn't buy an American-made brass surveying instrument because brass was not produced in America until 1837. Therefore, the instrument makers that were here made them out of hardwood. The most common wood was black walnut, cherry, apple and some of the cases made for Gurley instruments were made out of mahogany. (Gurley was a popular instrument and equipment maker first established in 1845 in Troy, New York still in operation today. )
Later, as the country developed westward, St. Louis, Missouri, became the area of instrument development. There were several instrument makers located there. One such maker was Jacob Blattner. When J. Blattner retired in 1872, Henry Blattner, his son who had been working with his father, took over the business together with his brother-in-law, Frank Adam. The St. Louis Directory listed them as Blattner and Adam. The maker of the American circumferentor, Adolf Wissler, who had been a worn and foreman for Blattner and Adam, took over the instrument business, which he continued until his death.
The first main instrument that surveyors used was the compass. Basically, in the United States it developed from the wooden compass, to the brass plain compass, to the brass vernier compass and from there to the transits. Today, some instruments are made out of aluminum.
But by the time Missouri and Arkansas were surveyed, there were very few wooden instruments used. Probably the first instrument used in this area was the plain compass, and if it was brass, it was probably imported. "On the plain compass you couldn't automatically set the magnetic declination," said Dave. "Because the magnetic pole and the true pole are different, we have to calculate what that is. Now the man that is running a plain compass has to know that the magnetic declination is approximately six degrees and thirty minutes. Everything he did, every line he ran, he had to add or subtract that six degrees and thirty minutes. So on the plain compass, you had to take that into account."
The early surveyors had other problems modern ones do not have because of the limitations of their instruments. One problem was with the magnetic storms that crossed over the United States. "The surveyors might set up one time of the day and read their compass, come back the next part of the day and it would be completely different, not much, but enough to affect the accuracy," explained Dave. "Because of the passing of the magnetic storms, the magnetic variation changes during the day, and it will change from morning to noon and back again at night."
Today, this solar compass's value is around $2,000.00. Mr. Krehbiel said it's value when it first came out was $210.00. The solar compass was more accurate than the standard compass. (Krehbiel)
[62]Another problem that the surveyor had when surveying Missouri was the iron fields that are located in the southeast part of the state which have some effect on the needles of the compasses. To minimize that problem, the instrument had to be all brass or wood--made of some non-magnetic metal. Even though the needle was made of iron, it had been highly magnetized, so this way you could use the iron needle.
The next step in compass development was the vernier compass, which was a more sophisticated instrument than the plain compass. This compass allowed surveyors to set the declination on the compass. The declination is the difference measured in degrees between the geographic meridian and the local magnetic meridian. Knowing what the declination was for the area, they would set the declination, lock it in, and then they could forget about it, for it would be automatically compensated.
Before the transit came in, there was a period from 1850 to 1860, when the standard compass was not allowed on government surveys. Surveyors were required to use a solar compass because it was more accurate. Since it came in so late, there was very little work done in Missouri with a solar compass. There are very few of these compasses today because they had a very short life span.
On the different styles of compasses there were different ways of reading lines. Some compass
faces were laid out just like a map, 
. But this posed a problem. When a surveyor turned his compass
northeast, the needle would read northwest. Since the needle always points north, it remains
stationary, but as the surveyor turns the compass, the needle appears to move in the opposite
direction. So, someone decided to reverse east and west, E N S W, so that when a surveyor
turned the compass northeast, the needle would read northeast, the direction the compass is
actually pointing.
The major change in instruments was from the compass to the transit which measures both horizontal and vertical angles with a small telescope that can be moved.
T. F. Randolph in Cincinnati, Ohio, around 1860, developed the new patent telescope compass, with patent telescope attachment for common compasses. This was an intermediate step. He developed the telescope to go on the compass to replace the open sights.
From this makers developed the transit to where surveyors could get vertical measurements. Surveyors could see farther more accurately.
The transit had a number of features the compass didn't. In addition to measuring horizontal and vertical angles, it was used for setting points in line (horizontally or vertically), for leveling operations, and as a compass (when provided with a compass needle). The transit was the kind of instrument an explorer would use the most.
Though the compass, or transit, was the most essential instrument in surveying, there were other pieces of equipment needed, such as a stand for the compass (jacob staff or tripod), measuring devices (chains, chaining pins), sighting poles and flags.
The following photographs illustrate some different types of compasses and transits in
chronological order. All these instruments are from the collections of Robert Elgin and Dave
Krehbiel. The name of the owner will follow the caption.
This instrument was made by Hart in the early 1700s before this country was a nation. Besides this one, there are two other instruments in a museum, and one of those is dated 1753. Since this instrument was not dated, it probably preceded the other ones. (Krehbiel)
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The only date on this compass, made by Goldsmith Chandlee and John Ordorf, was one that was scratched on the brass cover, 1817. Things scratched on the cover include a squirrel and a bird, and several names which are hard to read. It evidently had several owners. An interesting thing about this compass is the walnut case made to fit the compass. This compass could be used today, but the sights are missing. It is an example of some excellent workmanship. (Elgin)
This old brass compass was made by W. & L. E. Gurley around 1850. It's hard to tell the ages of a Gurley compass, because they made a lot of them. A lot of these Gurley compasses are still used today. (Elgin)
This instrument was made by Jacob Blattner of St. Louis, Missouri. The date of this compass is unknown, but it was used to survey the town of Morrisville, Missouri. Jacob Blattner retired from instrument making in 1872 when his son, who bad been working with him, took over. (Krehbiel)
After his father retired in 1672, Henry Blattner took over the business. He went together with his brother-in-law, Frank Adam. Together they formed Blattner and Adam, and made compasses far more advanced than J. Blattner had. This instrument was made between 1872 and 1891. It is a vernier compass with a telescope in place of open sights like other instruments. (Elgin)
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Adolf Wissler, the maker of this circumferentor, was a workman and foreman for Blattner and Adam. After they retired from the business, Wissler took over the company, which he continued until his death. This instrument is similar to the English-made one, but is more solid. (Krehbiel)
This circumferentor was made by the Jones Company, a private company in London, England. Very few of these instruments came over from England because of the expense of shipping and the cost of the instrument itself. People who settled the colonies were basically poor people who couldn't afford the expensive equipment. The man that owned this instrument was probably a wealthy surveyor. The circumferentor not only allowed the surveyor to run in one direction, but he could also run off on another line and measure the angle without moving or turning the outer sights on the instrument. He didn't have to disturb the instrument so that he could shoot another line in another direction on the inner sights. (Krehbiel)
This solar compass was developed by a man named Burt. After it came out on the market, other companies like Young and Gurley purchased the rights to build them. On setting up the solar compass, the surveyor had to do two things. The surveyor had to know what the latitude of the area was he was working in. So one adjustment was for the latitude of the area. The second step was to set off the sun's declination for the time of day. To do this he brought the sights of the compass approximately into the meridian or approximately north which he could read by the needle, and then he set the solar lenses into the direction of the sun. If the sun image did not fall between the lines, he turned the instrument horizon-ally until it did. (Krehbiel)
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This instrument made in 1853 by T. F. Randolph is a transition between the compass and the transit. Randolph developed the new patent telescope compass, with patent telescope attachment for common compasses. This particular compass was stored in a small leather case. Although the case is in a very poor condition, the label on the inside and the compass are in a good condition, considering their age and the lack of care they have had. (Krehbiel)
The 15" Wye "Y" Level on the right was made by Gurley around the 1900s or earlier. Used as a level, it determines the differences in the elevations between points. A graduated rod is used with the level. The level is used for establishing grades for highways, sewers, buildings and for other construction work. Unlike the transit, the level does not have to be set up over a definite point; it is set up at any place from which the rod may be seen and read. Therefore no plumb bob is needed. (Elgin)
The compass-transit, made by W. & L. E. Gurley around 1870, is a transitional piece between the old sight compass and the transit having elements of both--the compass and the telescope. It has a low powered telescope with a horizontal and vertical cross hair, but it doesn't have a horizontal circle to turn off angles and it has no vertical circle like a standard transit. (Elgin)
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Copyright © 1981 BITTERSWEET, INC.
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