Chain surveying scope — in traditional chain (tape) surveying, field work is primarily limited to which type(s) of measurement?

Introduction / Context:
Chain (or tape) surveying is the simplest form of surveying used for relatively small, level areas with uncomplicated details. Its economy and speed come from restricting field operations to direct distance measurements along straight lines and short offsets. This question asks what types of measurements chain surveying is limited to in the field.

Given Data / Assumptions:

• No theodolite or total station is used; angular work is not fundamental.
• Perpendiculars are set out with simple devices (cross-staff/optical square) but are treated as linear offsets from a chain line.
• Objective is to plot detail by linear ties and offsets to a framework of chain lines.

Concept / Approach:

Chain surveying relies on linear measurements only: chaining along baselines, tie lines, and check lines; taking offsets to locate features. Although devices like optical squares help set out right angles, the method does not involve measuring angles for computation in the way compass traverses or theodolite surveys do. Accuracy control is achieved by good layout (well-conditioned triangles/rectangles), check measurements, and adherence to limiting offset lengths for the selected plotting scale.

Step-by-Step Solution:

Verification / Alternative check:

Surveying texts define chain surveying explicitly as a method involving only linear measurements, differentiating it from compass/theodolite methods which are angular.

Why Other Options Are Wrong:

Angular only — contradicts the essence of chain surveying.
Both linear and angular — would describe traverses or plane-table with measured angles.
All the above — logically impossible.

Common Pitfalls:

Over-reliance on long offsets beyond the limiting length for the chosen scale; poor chain-line layout which reduces overall accuracy.

Final Answer:

linear measurements only