At Sitio Conte, province of Code, Panama, the 1940 Pennsylvania University expedition led by Dr. J. Alden Mason resumed, after seven years interruption, the field excavation begun by the Peabody Museum of Harvard University and described in the monumental memoir by Dr. S. K. Lothrop.

The use of every time and labor saving device (even a transit) was justified by trench temperatures at times exceeding 120 degrees. However, this description will assume that no transit was available: limiting working tools to a level, an opera glass, plumb lines, lantern, and measuring tape. A compass might have sufficed for laying out the north-south reference line but stars are more accurate.

Forty centuries before telescopes made possible a greater precision, the ancients were able to orient a pyramid true north within 3 minutes 23 seconds of arc, the error being about one part in a thousand. Ordinary engineer's transits are accurate to the nearest minute.