1848.] Observations made on a Botanical Excursion. 391 



from 56° to 79°. 5. Dew has been formed every night on the plains 

 since leaving the hill at Dun wall, the grass being here cooled 12° below 

 the temperature of the air. 



February 19th. — Marched up the Soane to Tura, passing some low 

 hills of limestone, between the cliffs of the Kyrnaon and the river. 

 Collected TJlmus integrifolia, a small Clerodendron, and pretty bell- 

 flowered Asclepiadeous plant crawling over the hedges. Botanized on 

 the banks of the river, which is lined with small trees of Ficus, Ter- 

 minalia, Pkyllanthus, Trophis, and various shrubs, one, a very sweet- 

 scented Vitex, with clusters of white flowers, also V. agnus-castus ? (or 

 Negundo.) On the shaded banks, abundance of a Mgosoteslike Cyno- 

 glossum, Veronice, Potentilla, Ranunculus sceleratus, Ramex, several 

 herbaceous Composites and Labiatce ; Tamarix formed a small bush in 

 rocky hillocks in the bed of the river, and in pools several aquatic 

 plants, Zanichellia, Naias, Chara, and a pretty little Vallisneria, and 

 Potamogeton. Riccia was very abundant. The Brahminy goose was 

 common here, and we usually saw in the mornings immense flocks of 

 wild geese overhead, flying. North elevation of Tura 443 ft. 



Here I tried again the effect of solar and nocturnal radiation on the 

 sand, at different depths in the sand, not being able to do so on the 

 alluvium. Temperature of air 87°. 



Noon. Daylight of following morning. 



Surface* 110° 52° 



1 inch 102° 55° 



■ 2 ditto 93°5 , . 58° 



4 ditto 84° 67° 



8 ditto 77° Sand wet 73° wet 



16 ditto 76° ditto 74° 



As from above Tura the Soane valley narrows very rapidly, I shall 

 give here an abstract of the Meteorological observations taken since 

 leaving the Dunwah Pass. 



The difference in mean temperature, (partly owing to the sun' s 

 approach) amounts to 2° 5 of increase on the Soane valley, above that 

 of the hills. The range of the thermometer from day to day was 

 considerably greater in the upper station (though fewer observations were 



* Thermometer employed not registered above this temperature. 



