Abstract: The inclinometer comprises a single module for measuring the inclination and azimuth of a bore, such as that of an oil well. The single module contains a removable cassette with an inclination measurement means disposed on one side thereof and an azimuth measurement means on the opposite side so as to provide a measurement recording on the substrate of the recording means. An optical assembly is provided within said module for the inclination and azimuth measurement means. Further, a power source is disposed within said module. The module has an inner and outer housing means being provided within said inner housing for providing a rotational movement thereto.In accordance with another embodiment, the inclinometer comprises a first module being a power module for supplying power to the components of the second module.