ACADEMY OF SCIENCES. 129 



vanccd. showing the existence of a broatl belt of extreme climate over Another 

 large portion of the earth 's surface ; and this, too at the time the whole of this con- 

 tinent and Europe and the western part of Asia were subject to unusual extremes 

 of temperature. I would first call attention to the diagram on the board showing 

 the curves of temperature between here and Yokohama in May last. In my 

 former conmiunication on the subject I stated that from the memoranda of ships 

 arriving in this port during the months of Xovember and December, there was 

 evidently an Equatorial current of air prevailing off the coast to the West, and 

 meeting the polar current at no great distance from the coast. The observa- 

 tions furnished by Capt. Doane show that the Equatorial current extended 

 across the Pacific, giving rise to an extraordinary high temperature, the mean 

 temperature for the voyage in November, which lasted twenty-five days,was 70.2°; 

 the extremes,with the exception of the coast climates, being 65^ and 77^, tempera- 

 tures which, at this season of the year, show the complete absence of any Polar 

 current. Although we do not possess any data as to what is the monthly mean 

 temperature of this portion of the earth's surface, yet there can be no doubt but 

 that this November temperature is far above the average mean temperature of 

 the month ; it is in fact nearly r)0 above the mean temperature of the middle of 

 summer, as furnished by the last voyage from the 22d of June to the 13th of 

 July. There can be no doubt, however, but that during the latter period the 

 temperature was probably as much below the mean as the temperature of No- 

 vember was above it, the unusual distribution of the atmospheric currents still 

 continuing, giving us the excessively hot summer we have been experiencing on 

 land, whilst an almost winter climate prevailed on the Pacific Ocean. 



On the same paper on which I have made a diagram of the temperature for 

 November, I have also made another showing the temperature across the 

 Pacific from the 1st to the 22d of May, a period during which we had an ex- 

 ceedingly high temperature over the greater part of the continent. In fact, the 

 temperature in the early part of May was higher than I had ever seen in this 

 country so early in the summer, and whilst we were so warm here, over the sur- 

 face of the Pacific a cold Polar current was prevailing, reducing the mean tem- 

 perature of the voyage 8.3o below that of the month of November. The same 

 anomalous temperature prevailed during the months of June and July, keeping 

 the temperature of what should be the hottest season of the year below that of 

 January. In making this calculation, the observations affected by the coast 

 climate have been left out. The observations furnished by Capt. Doane pre- 

 sent many other points of interest, which I hope to discuss at some other time. 

 I have brought forward these few remarks trusting that the strong evidence 

 they oftlr in support of the views I have before advanced, will direct the atten- 

 tion of meteorologists more particularly to the investigation of this branch of 

 the science, as it is, I believe, in this direction that we must look for its most 

 useful discoveries. 



By these observations, furnished by Capt. Doane, and other data, we can now 

 make a chart of the climate prevailing in the latter part of November and De- 

 cember over the largest part of the Northern temperate zone, embracing about 

 200° of longitude ; and although the data from Central Asia are somewhat un- 



