Method of squares
Also called: Grid square method · Topic: Maps and Map Scale · NCERT: Class 11, Ch 1 "Introduction to Maps"
Meaning
The method of squares is a simple way to find the area of a shape on a map. You put graph paper under the map and count the squares that fall inside the boundary. Count every whole square as one. Count the squares the boundary cuts through (partial squares), then halve that number. Add the two totals and convert the result into ground area using the map scale. The method is quick and needs no special instrument, but the answer is only rough.
Example
A student wants the area of Chilika Lake in Odisha on a Survey of India toposheet at 1:50,000. They lay graph paper under the lake and count the whole squares and the partial squares. They then use the 1:50,000 scale to turn the square count into square kilometres on the ground.
Don't confuse with
- Polar planimeter: an instrument that traces the boundary and reads the area from a dial. It does not count squares, and its answer is more exact.