WEATHER PROPHECIES. i 5 i 



aosolute, but relative to the preceding state of the weather. But also 

 these indications are valid for only a short interval before the actual 

 advent of the storm ; and in some instances, as in the Hyperborean 

 storm of the 2d and 3d of October, 1860, the interval is too short for any 

 advantage to be taken of the notice. The particulars of this storm, 

 which present in true character the difficulties which the meteorolo- 

 gist must encounter, are too interesting to be omitted, and we shortly 

 recount them from the complete and admirably-conducted investiga- 

 tion published by Prof. C. Piazzi Smyth, in the " Annals of Scottish 

 Meteorology for 1856 to 1871." The term Hyperborean has been em- 

 ployed to prevent confusion with tropical hurricanes ; it has also been 

 called, from its essential locality, the Edinburgh storm. We have to 

 consider only the practical lessons to be deduced from the observations 

 of this storm ; the account of the actual observations must be read 

 from the before-mentioned report of Prof. Piazzi Smyth. First, then, 

 the barometric notice was insufficient and too local to be of service, 

 while the storm was too quick in its movements. St. Hilda is the 

 most westerly station; and, even if the storm could have been tele- 

 graphed thence, the message would have allowed only two hours for 

 preparation, and would have arrived while the eastern men were sound 

 asleep. If a message could have been sent from Iceland the day pre- 

 vious to the arrival of the storm, many wrecks would have been pre- 

 vented. So that we see the present system of meteorology necessitates 

 not only diligent but earnest watching of the signals that should be 

 afforded by a net-work of cables and overland wires, for it is by a series 

 of connected observations, extended over a large area, that the useful- 

 ness of this branch of meteorology is alone likely to be advanced. 



But, it may be asked, what definitive knowledge can be gained, 

 say not of storms, but of average weather for some future period ? 

 Here we must again refer to Prof. Piazzi Smyth's report on the rock- 

 thermometers at the Royal Observatory, Edinburgh, and to the Pro- 

 ceedings of our own Royal Society for the 2d of March, 1870, in which 

 predictions of the weather during the winters of 1871-'72 are attempted. 

 The rock-thermometers have by their readings shown some well- 

 marked supra-annual cycles, the relation of which to the sun-spot cy- 

 cles will be known to our readers. And on this point it may be stated 

 that the Radcliffe astronomer announces, in his report for 1871, that 

 the mean azimuthal direction of the wind at Oxford, rigorously com- 

 puted from automatic records during the last eight years, varies year 

 by year through a range of 58 on the whole, between maximum and 

 minimum of visible sun-spots, the tendency of the wind to a westward 

 direction increasing with the number of spots, and with such west 

 wind, it is to be presumed, the amount of rain also. " The most strik- 

 ing and positive feature of the whole series of observations," continues 

 Prof. Piazzi Smyth, " is the great heat-wave which occurs every eleven 

 years and a fraction, and nearly coincidently with the beginning of 



