Much has been written about the height of waves, and as we approached the southern limit of our course and headed to the east, well below the parallel of Cape Horn, we got the full benefit of those constant westerly winds that blow around the world. Here the heaviest straight line gales are to be met with and the great fetch of deep water helps to produce magnificent waves of the first magnitude. Lecky, in his "Wrinkles," a book no sailor should be without, and a book no lover of the sea who likes to "be up" on things nautical should neglect to read, quotes Mr. Thomas Stevenson as the authority for an empirical formula that approximates the possible maximum height of waves, the same being considered as a function of the "fetch." This is given as a matter of interest, for working it backward it shows how tremendous the sea spaces through which the rollers that followed us had their being. The Stevenson formula is as follows: Height of wave in feet equals the square root of the "fetch" in nautical miles multiplied by the constant 1.5. Or, backward: the distance a wave has come equals its height, divided by 1.5, and the quotient squared. As the wind increased in strength the waves mounted until immense billows were formed that measured from 50 to 60 feet in a vertical line from hollow to crest. This was easily determined by mounting the shrouds and watching until the ship was in the trough, then noting the height of eye on a level with the wave crests. In reversing the Stevenson formula we find that for a 60-foot wave a fetch of at least 1,600 miles is necessary.[8]