Volume X, No. 2, Winter 1982
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
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.
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."
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.
Copyright © 1981 BITTERSWEET, INC.