The hand

Where it comes from

The tower's left edge on that sheet, traced and magnified fourteen times. The dashed line is where a ruler would have put it.

537units the edge runs

6.6units it covers, side to side

77units between one turn and the next

That is the whole finding. The hand is slow, not fine. A line that shakes at the width of itself reads as paper; a line that leaves true by six units over five hundred and comes back reads as an arm. The pen is fitted to both numbers at once and, read the same way, a 537 line in it covers 6.6 and turns back every 77 — the archive's hand exactly.

And what the sheet does not do is as much of the hand as what it does. It never doubles an edge — four strokes across the shaft, no pair. It never lifts on a long line — no gap in 537 units. It does not taper: at the plaza line's free end the pen is already at full width. Each of those was once in the pen, and each was wrong.

Measured at the stroke's centre, to a fraction of a pixel. Read to the nearest whole pixel instead, the same edge appears to turn every 63 — quantisation inventing direction changes that are not in the drawing. It is the kind of number that would pull the line tight and nervous if it were believed.

The three numbers

They live at the top of design/pen.py. They are the line — move one and every drawing in the identity moves with it. The specimen is the same plain figure each time.

They are in page units: what the drawing measures at the size it is placed. A sheet says what it is drawn in with viewBox and how big it is placed with width, and the hand converts once through the two. So the tower, drawn in a thousand units and placed at 640, and the bridge, drawn in sixteen hundred and placed at 1240, come out at the same weight — 1.94 and 2.01 on the page. Before the pen worked this way they were 1.62 and 2.02, and the bridge carried a hand-set fudge to hide it.

MEANDER 1.5 · CORR 40 · SMOOTH 12 · WIDTH 1.4 The hand. This is the line to match.

And what each one does

The same figure with one number moved. None of these is the brand; they are here so the setting can be recognised when it drifts.

MEANDER 0 No stray. A plotter, and the old mistake.

MEANDER 4.5 Strays too far. Careless, not careful.

CORR 14 Turns back too often. A tremor, not an arm.

CORR 500 One long bend. A bent ruler.

WIDTH 4.0 The pen too broad for the drawing.

Drawing something new

A drawing is a file, not code. Write the lines plainly, in any units, and the hand redraws them. One line in the file is one line on the paper. Nothing in pen.py changes, ever — that is what keeps every drawing the same hand.

<!-- chrysler.src.svg -->
<svg viewBox="0 0 1000 1000" xmlns="http://www.w3.org/2000/svg">
  <path d="M420,900 L420,300 L500,120 L580,300 L580,900"/>
  <path d="M300,900 L700,900"/>
  <text x="620" y="140">— 1046′</text>
</svg>

$ python3 design/pen.py chrysler.src.svg   →  chrysler.svg

patha stroke. line, polyline, polygon and rect work too, and so does anything a drawing tool exports as straight lines

lighta quicker, lighter stroke — cables, hatching, anything secondary

textwritten in the hand's own numerals, always at one height — 18 on the page, on paper or on a photograph

Everything else in the source is ignored, so guides, fills and colour can stay in the file and the hand will pass them by. python3 design/pen.py with no arguments redraws every source in the identity. The same source gives the same drawing on every machine, so a rebuild never churns.

Every drawing in the hand

Fourteen, and one pen: one drawing of each thing, placed at the size it was drawn. draw.py in each folder writes the source; pen.py draws it. On a photograph the same line is laid in the sheet's white.

landmarks/brooklyn-bridgeBrooklyn Bridge — slide 9, the cover, the landmark poster

landmarks/eiffelEiffel Tower — the cover, the landmark poster

landmarks/forthForth Bridge — the cover, the landmark poster

landmarks/sydney-harbourSydney Harbour Bridge — the cover, the landmark poster

landmarks/golden-gateGolden Gate Bridge — the cover, the landmark poster

landmarks/cn-towerCN Tower — the cover, the landmark poster

landmarks/petronasPetronas Towers — the cover, the landmark poster

landmarks/millauMillau Viaduct — the cover, the landmark poster

landmarks/burj-khalifaBurj Khalifa — the cover, the landmark poster

landmarks/one-wtcOne World Trade Center — slide 6, the mission page, the tagline board, the cover, the landmark poster

hand/specimenthe figure on this sheet

one-wtc/over-photoon the photograph — the site, the mission page, the tower poster

one-wtc/over-wideon the photograph — slide 8

brooklyn-bridge/over-photoon the photograph — slide 25

And on the posters

The same pen writes on the photographs: the checker's red on the joint and on the five material plates, the engineer's number on the nineteen material samples. posters/marks.py and posters/notes.py write them through redpen.py, which is pen.py in red or in white and nothing else.

joint/detailred pen — the checker on the gusset, the push, bend, pull poster