The Line of Collimation Method of Reduction of Levels is a technique used in surveying to determine the difference in elevation between two points. It involves measuring the vertical angles from the instrument to a series of points, known as sights, and calculating their differences in height.

The method provides a check on various aspects of the leveling process, including fore sights, back sights, and reduced levels. However, it does not provide a check on intermediate sights.

Explanation:

1. Line of Collimation Method:
The Line of Collimation Method is a commonly used technique in leveling surveys. It involves setting up a leveling instrument at a known point, called the benchmark, and measuring the vertical angles to a series of points along a line. These points are referred to as sights.

2. Fore Sights:
Fore sights are the measurements taken in the forward direction from the instrument to the next point along the line. These measurements are used to determine the difference in elevation between the benchmark and the next point. The Line of Collimation Method provides a check on fore sights by ensuring that the measurements are accurate and consistent.

3. Back Sights:
Back sights are the measurements taken in the backward direction from the instrument to the previous point. They are used to verify the accuracy of the fore sights and to detect any errors or inconsistencies. The Line of Collimation Method also provides a check on back sights, ensuring that they are reliable and consistent.

4. Reduced Levels:
Reduced levels are the calculated elevations of each point along the line with respect to the benchmark. These values are determined using the measured vertical angles and other relevant data. The Line of Collimation Method provides a check on reduced levels by verifying the accuracy of the measurements and calculations.

5. Intermediate Sights:
Intermediate sights are the measurements taken between the fore sights and back sights. They are used to determine the differences in elevation between consecutive points along the line. However, the Line of Collimation Method does not provide a direct check on intermediate sights. This means that any errors or inconsistencies in these measurements may go undetected unless additional checks or methods are employed.

In conclusion, the Line of Collimation Method of Reduction of Levels provides checks on fore sights, back sights, and reduced levels, but it does not directly provide a check on intermediate sights. It is important to ensure the accuracy and reliability of intermediate sight measurements through careful observation and additional checks to ensure the overall accuracy of the leveling survey.