34 Mr. F. Galton on Meteorological Charts. 



but also reproduces some of the features of discrepance presented 

 by the progress of the variation through the intermediate depths, 

 and therefore confirms the general accuracy of the preceding 

 results, for all the stations, so far as it might be questioned 

 because of only five years' observations having been available. 

 Further consideration of these results, and deduction of the con- 

 ductivities of the different portions of the earth's crust involved, 

 are deferred until after we have taken into account the further 

 data for Calton Hill, to the reduction of which we now proceed. 

 [To be continued.] 



V. Meteorological Charts. By Francis Galton, Esq.* 

 [With a Plate.] 



WHEN contemporary meteorological reports from numerous 

 stations are printed one after another in a column (such 

 as we may see in newspapers and certain foreign publications), 

 they present no picture to the reader's mind. Lists of this de- 

 scription are therefore insufficient to do more than supply data 

 which meteorological students must protract as they best can, 

 upon a map, in some notation intelligible to themselves, at a 

 considerable expense of labour and artistic skill. 



It is needless to enlarge upon the serious obstacle which the 

 necessity of doing this opposes to the pursuit of meteorology. 

 It has sufficed to convert what might be a very popular science 

 into a laborious and difficult study. We require means of print- 

 ing, not lists of dry figures, but actual charts which should record 

 meteorological observations pictorially and geographically, with- 

 out sacrificing detail. It is then in the belief that an attempt I 

 have just made to supply this desideratum might interest some 

 of your readers, and perhaps lead to useful suggestions, that I 

 forward the accompanying chart. (Plate II). It has been printed 

 with moveable types, which I designed and caused to be cast ; and 

 I am much indebted to Mr. W. Spottiswoode, who printed it, for 

 his aid in carrying out my ideas. The map simply incorporates 

 the newspaper data of the day to which it refers, and was printed, 

 not with any scientific object, but solely for the purpose of 

 experiment. 



Explanation of the Symbols. 



The shade signifies cloud, of an amount proportional to its 



depth. The types with lines round them, 



, stand for rain. 



Cloud types have been interpolated where observations were 

 * Communicated by the Autbor. 



