Any idea what the dots and letter/numbers represent in the Missouri River and slightly up the Platte? They are not township/range numbers. They appear to be defining the channel.
They showed you the good spots for bowfishing....
Not a clue and don't even have a good guess.
I was trying to make it some sort of latitude / departure between the dots, but that don't make sense assuming North is up.
I'm going to guess that they are a measurement of the width and depth at each location.
:good:
I was gonna say width and sounding (depth).
I think it would have to be maybe width in chains and depth in feet. Early Missouri River was actually pretty shallow, so that depth in feet seems a little too much. A lot would also have to do with the time of year. The image above seems to show a narrower width for 12 than it does for 8.
The Platte is very shallow as indicated by the modern image below just a short distance from the confluence with the Missouri. The small W numbers on the Platte do not match those on the Missouri when they are drawn the same width.
I think it would more likely be links than feet.
I think it is the width of the deep trough in feet of the river and the sounding in feet. River transport was a big deal and some aid to navigation accommodating piloting with the draft of a particular vessel which prevented boats from grounding. This would be a great aid in river cargo transport.
I.E. on the west fork of the lower scan. 2 foot Wide and 20 foot Sounding for the meander of the trough between the banks which is shown graphically.
In contemporary times lots of sedimentation has filled in most waterways while pumping of aquifers has reduced runoff that used to be velocity clearing sediment off the bottom and from deeper troughs.
The Platte River is a mile wide and a foot deep. I lived in "La Plata" before I moved to Puyallup.
Hot summer days; swimming in the cool water.....
I remember Merits Beach, back in the 70's....:music: You can lay in your yard and get a sun tan; but man i dig that warm white sand.....Merit's Beach! Merit's Beach!:music:
My guess is the primary channel width in chains and the depth of that channel in feet. The drawing probably depicts the width when at high bank level. The primary channel and it's depth would be critical to navigation. My only question is does the 10W, for example, represent total width or width from center line of primary channel to edge of primary channel. I believe this to be a navigation aid map.
I have seen the W by itself to indicate both water and width. S by itself usually means side or slope. I've never seen sounding without the lowercase d...
