284 SCIENTIFIC RECORD FOR 1884. 



as tliey have already learned to distiDguisli between the educated pro- 

 fessional physician and the uneducated quack.] {Z. 0. 0. M., xviii, p. 

 383.) 



104. Dr. A. Winkelmann states that in his previous work he showed 

 the results of verifying rain predictions by considering only how many 

 stations within the prescribed region for which the predictions were 

 made had rain at the appointed time. From this he showed how, 

 with the help of the knowledge thus obtained, we can so detiue the 

 boundaries of the regions for which predictions are made that the 

 separate stations in each group should have the greatest uniformity of 

 weather. He showed that a verification of or agreement as to rainfall 

 occurred at 85 per cent, of the stations, and that if all were divided into 

 two groups the most advantageous arrangement could possibly only give 

 87 per cent. In this work Winkelmann had considered only the occur- 

 rence of rain without considering its quantity. He now offers a short 

 study on the agreement of stations in any region as to the quantity of 

 rain, or what per cent, of the total annual precijntatiou falls on those 

 days for which these stations show a behavior different from that at 

 the majority of stations. To this purpose he selects thirteen stations 

 in Wiirtemberg, and first shows that for any station on 85.5 per cent, of 

 days its weather agrees with that of the ma;jority of stations. He then 

 shows that the total rain that falls on the remaining 14.5 per cent, of 

 the days amounts only to 5.49 per cent, of the total rainfall of the year; 

 and, again, that on a rainy day at any station, which is also a rainy day 

 for a majority of the stations, there falls 4.81 times as much rain as on 

 a day when its rainfall is not accompanied by rain at other stations. 

 He finally urges the importance of hourly or self registers, one of which 

 he has constructed. (J>. M. Z., i, p. 387.) 



105. W. Koppen, at the first regular meeting of the German Meteoro- 

 logical Association, Hamburg, jSTovember 18, J 883, gave a short account 

 of his new method of verifying weather predictions. In the same man- 

 ner as we examine the connection between different phenomena of na- 

 ture, so can we investigate the connection between predicted and actual 

 weather. Thus, if we count how often after a given prediction the 

 weather has any one of the several given characters, then must this clas- 

 sification show whether there really was any scientific base for the pre- 

 diction ; if there was no such basis the numbers indicating the actual 

 weather would show an entire independence of the prediction if a suffi- 

 cient number of cases be examined. His examples show that the tem- 

 perature predictions from day to day were sufficiently verified to justify 

 the belief in a rational system of predictions, but the predictions from 

 mouth to month afford no such conclusion. (D. M. Z., i, pp. 39, 40.) 



106. The Deutsche Seewarte states that our present methods of veri- 

 fying weather predictions, which had their origin in America [namely 

 at the Signal Office in 1871J, and which have been used in Germany since 

 1877, consist in this, that the individual predictions are analyzed into 



