CAMERA SENSORS
seven sizes at one scale, with the crop factor computed from the diagonal
SI BASE UNITS
seven constants given an exact number — and the seven units that follow from them
SI UNITS WITHOUT NAMES
the endless rest: assembled from the base and the named units, and never with a factor
SI DERIVED UNITS
twenty-two with names of their own — and what each one is made of
SI PREFIXES
from quetta to quecto · twenty multipliers
THE TALLEST BUILDINGS
the ten tallest at true scale — and where the floors in them end
THE WORLD'S TIME OFFSETS
37 offsets from UTC−11:00 to UTC+14:00 — a spread of 25 hours over a 24-hour day
THE AMERICAN WIRE GAUGE
forty-four sizes derived from two diameters and one law of progression
BICYCLE CLASSES
frame, wheel by ISO 5775 and handlebar — three signs of a class, and what the frame is rated for
CAR CLASSES
segments A to F by length and bodies by box count — how to name any car you see
MOTORCYCLE CLASSES
rake, trail, wheelbase and seat height — six classes drawn at one scale
PETROL AND DIESEL
nine lines of comparison, and in three of them the requirement is the same for both