Camper invented the "facial angle", a measure meant to determine intelligence among various species.

Camper's measurements of facial angle were first made to compare the skulls of men with those of other animals.

It presents no appearance of that prognathism which diminishes the facial angle.

It presents no indication of the prognathism which modifies the facial angle.

Prognathism, in anthropological language, means that particular projection of the jaw which modifies the facial angle.

In 1770, he conceived of the facial angle to measure intelligence among species of men.

One of the first to interest himself in comparative anatomy and paleontology, he also invented the measure of the facial angle.

Two lectures to the Amsterdam Drawing society on the facial angle (1770)

The facial angle, or gnathic index, is highly important in the study of anthropology.

He discussed the classical facial angle using the plaster cast of Apollo that was in the lecture hall.