Activity Feed › Discussion Forums › Strictly Surveying › Chain Notation

Chain Notation
Posted by BStrand on November 9, 2022 at 7:44 pmI remember there was a thread about this exact thing in the past, but I can’t seem to find it. I’m looking at an old plat and it is dimensioned in chains and some of the distances read 10.20 1/2. I’m forgetting how this was supposed to be interpreted. The half isn’t a link if I remember right. Can someone out there remind me, or possibly find that old thread?
Here’s an example of what I’m talking about:
jbstahl replied 1 year, 8 months ago 6 Members · 11 Replies 
11 Replies

Think we figured it out– the 1/2 appears to be 0.05 of a chain. Why they didn’t simply write it out that way I don’t know…

the 1/2 appears to be 0.05 of a chain.
0.05 chain is 5 links. Don’t you mean a half link = 0.005 chain?
The confusing one I recall a while back was about area.
. 
No, what I mean is the 8.60(1/2) is actually 8.65 chains. When I draw the plat out this way it misses closing by about half a foot which is probably as good as it gets in 1911.
Elsewhere in the plat they show a ROWs as 45(1/2) which obviously isn’t chains, but works out to 30′ when calculated as links.
Clearly this guy didn’t have the same teachers I did because the easiest way to get your homework shredded was to mix units and not tell anyone. ???

Elsewhere in the plat they show a ROWs as 45(1/2) which obviously isn’t chains, but works out to 30′ when calculated as links.
The 1/2 in your ROW 45(1/2) example is 45.5 links which is 30.0′. The 1/2 is 1/2 of a link which is 4 inches.
The plat dimension 8.60(1/2) would, therefore, be 8 chains and 60.5 links or 568 feet.
JBS

I’ll try to attach a full copy so y’all can see what I’m talking about.

8.60(1/2) is actually 8.65 chains.
45(1/2) works out to 30′ when calculated as links.
I can’t see how you can use two different interpretations of the notation on the same drawing. I agree with JBS that it has to mean 1/2 link, and there is some other problem with the first length.
. 
The county surveyor’s record in my home county has similar notation. This survey is from 1887. I’m pretty sure that 40.26.4 chains shown here is is equal to 40 chains, 26.4 links which is equal to 40.264 chains.
I would think that 8.60?« chains is 8 chains, 60?« links or 8.605 chains.

@jbstahl What am I doing wrong? 45×8″=360″=30′ so 45.5=30’4″ not 30′ as you say in your post.
If 451/2 means 45 and a half links then that is 0.455 chains which equals 30(.03) feet. The precision is on the 0.33 foot level so the 0.03 is not significant.
A link is about 7.92″ precisely.
Log in to reply.