38 repokt — 1877. 



ference 'beats'. These 'beats' are heard also if the forks be held one to each ear, 

 or if their sounds be conveyed separately to the ears with pipes. No combinational 

 tone is heard, however, when two forks of an interval of a fifth, third, or fourth 

 are held to the two ears and the intervals are harsh. A minor third produces thus 

 an intensely disagreeable sound. When two tones in unison but differing 180° 

 in phase are led to the two ears there does not appear to be any mutual destruction 

 of the tones, and both are heard. As there is no physical decussation of the auditory 

 nerves after leaving the fourth ventricle of the brain, the inference appears to be in 

 favour of a means of comparison existing within the structures of the brain itself. 



Meteorology. 



On some Relations of Sea and Land Temperature in the Souih-ivest of England. 



By Db. Barham. 



The intention of the author was to furnish some materials for a correct estimate 

 of the reciprocal influence of land and sea on the temperature of the air in the 

 South-west of England, and inferentially on that of the more eastern districts. The 

 physical geography of the promontory of Cornwall and the Scilly Isles rendered 

 them interesting for their meteorology, and also as a scientific instrument from 

 Nature's workshop, hardly to be equalled elsewhere for displaying, and to some 

 extent measuring, the operation of most of the factors of climate. The stations 

 of observation were St. Mary's (Scilly), Penzance, Helston, St. Agnes, Truro, Ply- 

 mouth, Guernsey, and Greenwich, the latter as a generally recognized central 

 standard. The observations extended over four years. The mean highest 

 temperature was the same at Scilly and Penzance, namely, 71° Fahr. ; at Guern- 

 sey, which came next, it rose to 72°-70 ; at Helston it approached 79° ; at Truro it 

 was nearly 78° ; and at Plymouth 74°. The mean lowest temperatures were St. 

 Mary and Penzance, again almost the same, 59°; Guernsey, 61°; Truro, 56-8°, nearly 

 the same as Greenwich. The absolute highest temperatures at Scilly and Penzance 

 were again much alike, namely, 74° and 75° ; Helston and Truro, 86° and 85° ; Guern- 

 sey, 785°, while at Greenwich it reached 91°-8, so that there was a difference of 16° 

 between the extremes of Scilly and Greenwich, and of 12° between places almost 

 adjacent, as Penzance and Helston. The absolute lowest summer temperature showed 

 a similar relative equability. With regard to sea temperature, it' was stated that the 

 mean temperature of surface-water at Scilly and round the Cornish coast in the height 

 of summer was 60°. Its influence was well shown in abstracting more than 8° from 

 the average heat of hot days in the ten miles between Helston and the shores of 

 Mount's Bay. There was scarcely any difference between Penzance and Scilly, in ' 

 consequence of the almost island character of the peninsula ; but immediately they 

 got beyond the estuary, they got to a mainland climate, Helston being much higher 

 in summer and much lower in winter. That was the great reason why Penzance 

 was so suitable as a health resort, its climate, though not identical with that of 

 Scilly, having still a great analogy to it. The extreme cold recorded at Penzance 

 during 50 years was 23° ; occasionally, but very rarely, it fell to 26° ; and at Scilly 

 it was rarely below 29°. The mean temperature of the sea in the winter months 

 was 50° ; and this, it was seen, penetrated the extreme of cold in winter in the 

 same way as it did the extreme of heat in summer. In the course of further obser- 

 vations Dr. Barham showed how much further inland the influence of the westerly 

 winds extended than that of the east winds. 



Difference of Rainfall ivith Elevation. By G. Dines. 



On the Measurement of the Height of Clouds. By A. Mallock. 



