METEOROLOGY. 225 



above curve, they do not invalidate the view I advanced in a former 

 letter about the nature of this cuive, as it ought to be in its normal 

 value. In their main features both coincide, if we make due allow- 

 ance for the short period during which these observations have been 

 continued. The curve in diagram No. 10 having its first maximum 

 near the 18th of May, its minimum near the 8th of July, and its 

 second maximum near the 2*7th of October, and if we were to draw a 

 mean line between the heights of 1856 and 1857, the second maximum 

 would be near the 3d instead of the 27th of October. 



No. 11. In order to compare the course of the morning temperature 

 of Colonia Tovar with that of some place of the southern part of the 

 United States, I have in diagram No. 11 laid down in dotted line the 

 course of the temperature at 7 a. m. for the different days of March,,, 

 1852, as observed by me at Memphis, Tennessee, with the same ther- 

 mometer with which I made my first observations at Colonia Tovar. 

 The other line is the course of temperature at 7 a. m. for the different 

 days of March, 1857, at Colonia Tovar. 



Besides the regular observations specified above, I have made from 

 time to time, just as occasion offered, memoranda on many other me- 

 teorological subjects which came under my observation. These memo- 

 randa were made either at the time of observation or immediately 

 after. They are rather numerous, and for want of time I am unable 

 at present to arrange them properly, or to make a selection from 

 among them. 



I may^ however, afford so much time as to give the following : 



July 27. In pre}taring for a journey to La Victoria, I rose early in 

 the morning. At 4^ a. m. there was a dense fog. Intending to step 

 out, and opening the kitchen door which leads into the open air, I 

 saw the sprightly burning kitchen fire reflected from the fog as from 

 a white, smooth, and solid wall ; and, besides this, a halo of about 

 twenty feet diameter, as plain and well defined as I ever saw around 

 the moon. This halo, with the reflected fire in its centre, appeared 

 to be close before me in a vertical plain, and it changed its position 

 whenever I changed mine, either to the right or to the left. 



At a first superficial glance upon the map it may seem as if the 

 northern coast of Venezuela, on account of its great distance, can have 

 nothing to do with the climate of the United States, or that the me- 

 teorology of the two countries can have no feature common to both ; 

 but observation proves it to be otherwise. And if we take a more 

 comprehensive view of this vast region, we see that the Mexican gulf, 

 together with the Caribbean sea, is nothing more than a great inland 

 sea basin with numerous and spacious entrances to the northeast and 

 east. Five States of the Union forming its northern shore ; Venezuela, 

 New Grenada, and Central America, its opposite or southern shore. 

 Here I may also remark about the Venezuelan mountain range of the 

 coast, that its northern declivity towards the sea is generally very 

 steep, and in many places near its crest bearing marks of immense 

 masses of its body having sunk on that side far below its original 

 level, while on the other or southern side, no such marks are visible. 



If we want to study in Venezuela the mutual influence of atmos- 

 pheric currents of these two opposite shores, viz : The southern coast 

 15 s 



