Land Boundary Monuments, Past and Present (5 of 6)
Mr. Thorpe also used a large number of cast iron monuments that I have never seen in any other area. This monument was about 20 3/4 inches long, with a 3 1/2 inch diameter base and a 1 3/4 inch diameter hemispherical top. The top and the base are connected with a tapered stem with a cruciform cross-section with 1/2 inch webs. More than thirty years ago I was retracing a line which Mr. Thorpe had run and the notes called for a cast iron monument (C.I.M.) set at a sixteenth corner. The point fell in a fence line at an ancient red cedar corner post. I assumed the monument was by the post, and spent a good amount of time trying to find it. I found nothing but the post. A creek ran parallel to the north-south fence about a hundred yards away. About six years ago I was asked by a landowner on the creek to do some work on his lot. He had been clearing the property and had found a pile of scrap metal on the bank of the creek, which he had thrown up by the foot bridge. There was an iron buggy step or so, miscellaneous scrap which a farmer might have collected, and AN UNBROKEN COUNTY CAST IRON MONUMENT (shown in photo above). As we see now and then, the farmer apparently removed the monument and set his corner post at the "exact point." Another monument which Mr. Thorpe cited and which I found was a sleigh shoe, which was a slightly curved steel strap about two inches wide and 1/2 inch thick. (See similar sleigh shoe in photo above.) Another monument that he cited in several books and I have found was the wagon skein. Early wagons with wood spoke wheels had a wood axle with an iron cone on each end called the thimble. The hub of the wagon wheel was placed on this thimble. A cast iron truncated cone (the skein) was placed inside the hub as a bearing surface for the thimble. This skein might be ten inches or more long, with an average diameter of three inches, and a wall thickness of a quarter of an inch, depending on the size of the wheel.
As with the county cast iron monuments, these were buried and not driven. You will seldom see a skein in scrap piles, as they usually remain in the wood wagon hub. The skein would not appear to be a satisfactory monument, but these still survive.
Let me digress a little. I retraced a section that Mr. Thorpe had surveyed in the 1890s, and his notes called for a "gun barrel" (not the one cited above). This was in an area off of the beaten path. I found the barrel in place. This is the interesting part of the story. From Mr. Thorpe's notes we know that he worked around the military reservation of Fort Ellis, just east of Bozeman. We also know that the salvage party sent out to the Little Bighorn battlefield site after the massacre of Custer and his men was sent from Fort Ellis. What I found was the barrel and receiver of an 1873 Springfield trap door rifle similar to those used by the Seventh Cavalry, with the date and eagle clearly visible. If a damaged rifle was recovered and consigned to the scrap pile at Fort Ellis, there is a possibility that this was the origin of the "gun barrel" which he noted. I have not been back to that area, and hope that it has been left in place.
Around the middle of the 20th century the use of sections of steel concrete reinforcing bars came into use -- these range from a very occasional 1/4 inch (No. 2) pencil rod to the very occasional 3/4 inch (No. 6) bar. Generally I find the bar to be 1/2 inch in diameter, with currently more 5/8 inch diameter bars being used. (It is helpful in preparing a plat showing found bars of this type to fully describe the bar, giving not only the diameter but also the deformation pattern and type of cut. Deformed bars may have a slant pattern, a ladder pattern, an X pattern, or an arc pattern. The bar may have been sawn, clipped, or cut with a torch.) These bars often have several wrappings of ribbon on the top, which give a history of the recovery of these monuments. Although you may have to dig down a little to find the type of deformation, I do not believe that these wrappings should be disturbed -- added to, perhaps, but not removed.
Until about 1965, no identification appeared on the bar. At about that time, cast aluminum caps with a diameter of about 1 1/2 inch appeared on the market. Many of the bars available at that time (before the advent of cut-off blades) were sheared in the shop, and it was necessary to remove the burr by grinding or filing. If this were not done, the cap would often split.
In the seventies aluminum caps were swedged, and were considerably more malleable than the first cast caps. These are available in diameters ranging from 1 1/2 inches to over 3 inches. The caps with diameters of 2 inches or more were usually furnished with plastic liners. With exception of special order caps (such as the 2 inch octagon cap that one company could supply for use in Texas) all caps are round. (The seal of the Texas surveyor is octagonal.) Brass caps with plastic liners are also currently available, and have a very professional appearance. Aluminum caps that are buried can corrode. Brass caps are considerably more durable, but more expensive.
The identification of the surveyor on a survey cap has been state law in Montana since 1973. At that time the law required that the surveyor's name or number be on the cap. Unfortunately, some companies purchased caps (often the little yellow plastic ones) with the company name, and these were used by all surveyors employed by that company. Recently the rule has been revised and the number of the responsible surveyor must appear on the cap. In Texas, a recent rule requires surveyor identification on the monument.