IN a previous article (vol. lxxiii. pp. 54–56) we described our expedition to the tropics, and gave the results of the observations with balloons and on mountains, so far as they related to the movements of the upper currents. In the present article we will consider the observations with kites, which furnished nearly continuous records of temperature, humidity, and wind velocity from sea-level to a height of 2300 metres, and the direct observations to a greater height which Mr. Clayton obtained in ascending and descending the tropical peaks on the islands of Teneriffe and Fogo. During a voyage of the White Star steamer Romanic, from Boston to Gibraltar, Mr. Clayton executed six kite-flights, and on board the steam-yacht Otaria, between latitudes 37° and 10° N., longitudes 16° and 31° W., with the assistance of M. Maurice, seventeen kite-flights were made, besides two in the harbour of Santa Cruz to investigate the sea breeze, and one in latitude 43° 43′N., longitude 8° 43′ W., for the study of the changes in the free air produced by the total solar eclipse. The observations obtained at the height of 1000 metres, compared with those at sea-level, are given in Tables i. and ii. The first table ctains the observations made in a general east and west direction between longitudes 69° and 16° W., latitudes 42° and 33° N. West of the Azores, that is to say, on the westward slope of the permanent area of high pressure, the decrease of temperature with height was slow, there being two cases out of the four in which the temperature increased immediately above the ocean, the average decrease in the thousand metres being but 0°.41 C. On the eastern and southern slopes of the high pressure the temperature decrease approached the adiabatic rate, amounting on the average to 0°.73 C. per hundred metres. The relative humidity diminished with altitude over the western barometric slope and increased in the observations obtained over the eastern slope, while the wind veered and increased with altitude in the former locality and backed with diminishing velocity in the latter. Fig. 1 shows the typical vertical distribution of the meteorological elements to the westward of the Azores.