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dialing toward the sky. This effect must be 

 scarcely sensible on account of the cloudy state 

 of the atmosphere. It appears also, that the 

 elevation of the site of Javita contributes to the 

 coolness of the climate. Maypures is probably 

 from sixty to seventy toises above the level 

 of the ocean, San Fernando de Atabapo one 

 hundred and twenty-two toises, and Javita one 

 hundred and sixty-six toises. The little atmos- 

 pheric tides varying on the coast (at Cumana) 

 from one day to another from 0*8 of a line to 

 two lines, and I having unfortunately broken 

 the instrument before I again reached the shore, 

 I am not quite sure of these results. In mak- 

 ing observations at Javita on the horary varia- 

 tions of the atmospheric pressure, I discovered, 

 that a small bubble of air intercepted* a part 

 of the column of mercury, and modified by it's 

 thermometric dilatation, the effects of the tides. 

 In wretched boats, and encumbered as we 

 were, it was almost impossible to hold the baro- 

 meter in a vertical position, or much inclined. 

 I took advantage of our stay at Javita to re- 



* I relate this minute circumstance, to remind travellers 

 how necessary it is, to have barometers, the tube of which is 

 visible throughout it's whole length. A very small bubble of 

 air may intercept half, or even the whole of the column of 

 mercury, without the sound of the mercury striking against 

 the extremity of the tube being changed. 



