CHAPTER IV

Above a tiny little writing-desk fixed to the wall of the conning-tower there was a square mahogany board with six white buttons in pairs. On one side of the board hung a telephone and on the other a speaking-tube. To the right hand opposite where Zaidie stood were two nickel-plated wheels and behind each of them a white disc, one marked off into 360 degrees, and the other into 100 with subdivisions of tens. Overhead hung an ordinary tell-tale compass, and compactly placed on other parts of the wall were barometers…