Sumit Enterprises

A prismatic compass is a surveying and navigational instrument used to determine the bearing of a line and calculate angles between lines in a traverse. It's characterized by a prism, which allows for simultaneous sighting and reading of bearings, making it efficient for field use. Here's a more detailed explanation:

A Vernier theodolite is a surveying instrument used to measure both horizontal and vertical angles, with its defining feature being the use of Vernier scales for reading the graduated circles. It's also known as a transit theodolite because its telescope can be rotated (transited) 360 degrees in a vertical plane. While less precise than modern optical or digital theodolites, it's still widely used due to its simplicity and lower cost. 

An electronic theodolite is a precision surveying instrument used to measure horizontal and vertical angles. It's an evolution of the traditional optical theodolite, utilizing electronic sensors and displays to provide angle measurements. Key features include photoelectric sensors for reading circles, rechargeable batteries, and robust protection against water and dust