(NEWSER) – When you picture Egypt's pyramids rising over the country's sands, your vision likely doesn't include water. It should, according to a new study published online Tuesday. University of Amsterdam researchers found that ancient Egyptians employed what Phys.org calls a "clever trick" to facilitate the pyramids' construction: They likely wet the sand along the path they dragged their sleds, which were laden with pyramid stones weighing some 2.5 tons, reports Gizmodo. This greatly lessened the power needed to pull the sledge from the quarry to the construction site—so much so that the number of people needed to pull the sledge could be cut in half. Assuming the right amount of water was used, that is.