292 POPULAR SCIENCE MONTHLY. 



Such was the condition of observational meteorology in America at 

 the time when Mr. A. Lawrence Eotch conceived the idea of establishing 

 a meteorological observatory on the Great Blue Hill, near Boston. At 

 first Mr. Kotch intended to use this observatory for special investiga- 

 tions, leaving the regular work to Signal Service observers. As no plan 

 of cooperation with the Signal Service was found feasible, he deter- 

 mined to carry on the entire work under his own direction and at his 

 own expense. 



Mr. Eotch was particularly fortunate in his choice of a site for his 

 observatory. Although the summit of the Great Blue Hill is but 635 

 feet above sea level, yet it possesses many of the characteristics of a 

 mountain. It is the highest point of land in eastern Massachusetts, and 

 offers an unobstructed view for many miles in all directions. This 

 feature has been particularly valuable in prosecuting cloud studies. 



The Valley Station ok Blue Hill Observatory. 



The location is so near the coast that the characteristic water and land 

 influences on the atmospheric conditions can be perceived. Moreover 

 the summit of the hill is near that critical altitude at which the diurnal 

 variation of the wind changes from the low level type to the high alti- 

 tude type. We had meteorological records from the Signal Sei'vice sta- 

 tions on Mt. Washington (altitude about 0,000 feet) and on Pikes Peak 

 (altitude about 14,000 feet), but we had none from the lower altitude 

 at which the powerful local influence of the ground surface ceases to 

 be overpoweringly effective. Thus this observatory fitted into a vacancy 

 which it was desirable to fill. Nor is this all. The wonderful success 

 attending the recent extension of the work of the observatory to the 

 exploration of the upper air by means of- kites has been in no small 

 part due to the perfect adaptation of this locality for carrying on such 



