how old is my historic house?

I wonder if anyone can help me find out the age of my historic house in port washington, NY. It was a farmhouse later converted to an estate residence. While doing a small renovation this summer on the entry, I uncovered an older beam and post construction on the section where the farmhouse was. It is a mortice and tenon framing in heavy timber with a wooden peg thru the joint. also, each joint is marked with roman numerals chiselled into each piece of the joint.The timber looks like a dense pine of some sort. The farm was sold in 1900 and I wonder if the post and beam structure dates from before or after this time.

Rob,

Very little question your house, and probably barn, are much older than 1900. Maybe 100 years or more. The Roman numerals you mention at the joinery are "carpenter's marks", sometimes called "marriage marks". They are the marks left by a carpenter trained in "scribe rule" layout of timber frame (mortice and tenon) buildings. This ancient system is still in use in Europe today and came to America with the colonial settlers.

Around 1800 a system of layout now known as "square rule" began to replace scribe rule. This new system didn't use the archaic carpenter's marks. By the Civil War scribe rule layout was effectively extinct.

I would strongly recommend working with someone knowledgable in these searly building methods as you take on the stewardship of you homestead.

Rudy R. Christian

Also have a look at the beams themselves. Hand hewn usually indicates an older structure. Sawn beams with vertical saw marks a little newer, sawn beams with circular saw maks after ca. 1850. Even after people started sawing their timbers some of the really long ones may be hewn (due to saw mill constraints) or have been salvaged from an earlier structure.

If it is scribe rule frame you may also find the master compass settings (circles) scribed into one of the beams. These were used to refernce the compass settings throughout the buildings construction.

Hi mad professor

Could you elaborate further on what you refer to "the master compass setting".
I have never heard of this before, and i am sure many others haven't either
Thanks
NH

Hi Northern Hewer,

I learned about the scribe rule compass settings from Richard Babcock and pictures in his books from very early structures (1600s, 1 possibly 1500s) he restored.

These really early buildings were laid out using scribe rule. Each beam (size), brace, mortise and tennon were laid out using chalklines (charcoal lines), plumbbob, and compass (divider). The compass would be set for different circles for different layouts. The master builder would scribe these circles as a reference so that when for instance the same size tennon needed to be laid out again there was a reference to set the compass (divider). Yes, you would still have to test fit joinery but it's really an amazingly accurate way to layout joinery.

Anyway these "master settings" were scribed onto one of the principal timbers as a reference, usually as a series of concentric circles. These were used not only in building the structure but also if repairs were needed and a timber needed to be replicated.

You can also layout all your angles using a compass, i.e. perfect 30, 45, 60,90 angles. To square up two beams to be joined at 90 a 3,4, 5 right triangle was used, the lenght of each side corresponding to 3,4, and 5 "turns" of a particular compass setting.

Hi Northern Hewer,

I dug out some references to master buiders marks left on old structures:
1) Richard Babcock, Old Barns in the New World; Berkshire House Publishers: Lee Ma, 1996, pp.60-61, p. 151-152 (possibly 1500s Chapel),
2) Richard Babcock, Barns Whose Roots Run Deep; (no publisher listed), 2004, p.27, p.36, p.38, p.41, p.58,
3) Richard Babcock, Barns; Researched, Restored, and Resurrected Using Ancient Methods; (no publisher listed), 1998, p. 13b, p.21 (possibly 1500s Chapel)

The above also have lots of pictures/info on "the bull wheel" (capstan) and gin poles used in raising very large structures by hand.

If you can't find the above and are interested, email me, I know Mr. Babcock and can put you in touch for the publications (I watched him hew a beam yesterday!, He's in his 70s and still going......)

Best regards,

Mad Professor

When I first read this, I thought you meant compass setting like north, south, east, and west. But what you're talking about are circles scribed into a timber by using a set of dividers.
A compass in the drawing world has a pencil on one leg of the divider, to draw an arc or circle.
Sometimes we need to define our terms so others can understand what we mean.
Taking "turns" down a timber is usually done with dividers as each leg has a very sharp point, unless I'm totally mistaken.

Jim Rogers

PS. I have #3) Richard Babcock, Barns; Researched, Restored, and Resurrected Using Ancient Methods; (no publisher listed), 1998, p. 13b, p.21 (possibly 1500s Chapel) great book.

Hi Jim,

I used the word "compass" interchangibly with divider as that's the term Mr. Babcock used in my conversations with him. I can see where it may have caused some confusion.

BTW, I did use a compass (the one with a pencil) for my first scribe rule project (just to practice layouts). I made up a wood rack out of irregular 4" X 4" stock, all mortise and tennon and pegged together. Still has the penciled in circles showing........

Mad Professor