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KEW OBSERVATORY AND METEOROLOGY 239

divergent spikes directed towards each of the sixteen primary points of the compass, whose several lengths are proportional to the frequency of winds in their direction. A shade or other sign shows the proportion of the winds above a specified strength. Consequently the roses afford means for judging which of two competing courses receives, on the average, the . greater share of favourable winds. But it is no easy matter to calculate by mother-wit the relative efficiency of the winds as expressed by roses, upon the run of a ship along any particular course. Almost every wind can be utilised to some degree ; we want to know the aggregate effect in the required direction of the average of the winds from all the sixteen primary points. I showed how this could be found mechanically for any ship whose sailing qualities were known, and suggested that "passage roses " should be calculated for a typical vessel wherever wind roses existed. I think this would have been taken in hand, had not steam begun to largely supersede sails, and was doing so at a rapidly increasing rate.

I was rather scandalised by finding how little was known to nautical men of the sailing qualities of their own ships, along each of the sixteen points of the compass, assuming a moderate sea, and a moderate wind blowing steadily from one direction. I think, if I had a yacht, that this would be the first point I should wish to ascertain in respect to her performances.

When the Meteorological Council was established, its first President was that most accomplished classical scholar, as well as mathematician, Professor Henry