a paire of compasses

I have some unanswered questions from last week…I’ll get to them, and for now here is one about the compass I use to layout many of my carved patterns.  Mine is quite simple, and fairly stout. That way it doesn’t wiggle at all. I have had some in the past that the shanks, or legs, were too thin & could flex. I sharpen it with a file, just eyeballing the points; might sharpen it twice a year, maybe a little more. It has a fine adjustment screw that I never use, I just use the thumbscrew that pins the leg against the semi-circular piece.  If you are looking to buy old ones, I would say look for those with thicker legs like this one; I have shelved the compasses I have with thin flexible legs.

PF compass

In use, for me it’s a two-hand job. I keep the stationary leg still with one hand, and use the other to swing the arc I need. it might seem fussy to use a compass this way, but I don’t want to strike a line in the wrong spot, the eraser is a plane…

striking an arc

Some of the period sources – Here’s Moxon, with little to say. He does describe its use in a few places, the one I remember best is marking out timber to be sawn.

“Of the Compasses marked E in Plate 5.

aa The Joint, bb the Cheeks of the joint, cc the Shanks dd the Points. Their Office is to describe Circles, and let of Distances from their Rule, or any other Measure, to their Work.”

Then Randle Holme. His first bit sounds pretty familiar:

…a Pair of Compasses, … The Joynt is the place where the Compasses move and turn; The Cheeks of the Joynt is where they go in one to the other; The Shanks, The Points

But when he illustrates them, he describes several kinds. Some tool historians make a big deal out of the distinction between compasses and dividers; I think generally the idea is that those that can be fixed in position are dividers; but note that here Randle H0lme says these dividers “are Compasses which open…” so forth.

Holme's circle dividers

a Pair of Sliding or Circle Dividers, these are Compasses which open upon a Brass semi-circle, and by a small screw is made fast at any station.

Holme screw dividers

a Pair of Screw Dividers, or Pointed…  These are Compasses opened and shut with a screw, so that there is noe danger of their moveing from their station. By all these foresaid Compasses, are described Circles, Ovals, &c, and also Distances are measured and set off from the Rule, or from any other divided Rod or Staffe, to the thing to be wrought upon.

Remember the Stent panel, both workmen depicted there have their own set of compasses, hanging on the wall behind them:

Stent panel

Alexander is always after me about the term “compass.” In the seventeenth century, it’s mostly called “a paire of compasses” – but you do sometimes see it mentioned as “a compass.”

Here are some tools listed in a Bristol, England apprenticeship contract:

1611  Thomas Thomas to Thomas Phelpes Howsecarpenter & Marie:

. . one axe one Addys two Chezilles one Mallet two boorriers one Squire & one Compasse one joynter one foreplane one Rabbett plane on bowltle plane & one Cadgment plane one smoothing plane . .

And a cooper in Salem, Massachusetts, 1654:

George Williams, Salem 

          In Coopers timber 6£-10   3 axes 6s & 3 Coopers axes 12s 

3 frowes 5s  a hatchett & bill 2s  4 addses 15s  8 Drawing knives 10s  2 augers & bung borers 2s  3 pr Compasses 3s  2 Round shaves & an ould Adds 3s  1 handsaw 12d  2 thwart Sawes 10s  3 howells 3s  percer bitts 1s6d  2 Joynters 4s  Trussing hoopes 2s  2 Cresses 2s6d  2 Cressetts 5s  a grindstone 2s  100 hewed staves 5s