*It is conceivable that a major weather change in Egypt could result in sufficient drying of the pyramids over the course of a few decades (or centuries) so as to decrease the RF losses sufficiently to permit successful probing of the interiors bu this radio-wave technique. Artificially drying the pyramids would be novel but is clearly not practical. The pyramid of Chephren, weighing as it does about 10¹⁰ lb, contains about 100 million gallons of water!