24 THE LIFE OF JAMES D. FORBES. [CHAP. 



the outside of the hill, opened within the last forty days, 

 whence very hot air rushes with great rapidity and in 

 such a degree as to make ferns blaze, though they were 

 quite damp. Kesuming the edge on the summit, we 

 returned as we had come, to the top of the descending 

 path ; and having eaten our roasted eggs, which were 

 excellent, we went down to the hermitage, where we took 

 the cold dinner we had brought with us. Vesuvius is 

 now, about 3,400 feet high ; formerly it was 4,250, but 

 in the prodigious eruption of 1822 more than 800 feet of. 

 the cone were thrown off. At eruptions in general, and 

 that of 1822 in particular, the most tremendous thunder 

 and lightning ever remembered by Salvatore, or his father 

 before him, attended to give more force to the scene ; the 

 sea retires from its troubled bed, while shells in masses 

 are thrown from the volcano. The weight of the ail- 

 diminishes by whole inches of mercury. There is a vast 

 unison and sympathy of all the powers residing in the 

 earth, and of those most especially affecting the constitution 

 of our globe derived from the heavens. Electricity, and 

 consequently magnetism, the equilibrium of the atmo- 

 sphere, the level of the ocean, the effects of weather, the 

 reservoirs of internal fire in all parts of the globe, the 

 influence of the moon itself, are all employed, affected 

 by, or brought to the aid of this vast production of the 

 mechanism of nature. Surely it is not too much to 

 say that some indissoluble bond unites these various 

 agencies, which perhaps it is the lot of this age to dis- 

 cover. If connection exists, and should the latent 

 principle be discovered, it is impossible to foresee how 

 great may be the extension of human intellect, how 

 deep our insight into the physical economy of all that 

 surrounds us/ 



On November 29th he watched and recorded the 

 appearance of an eclipse of the sun at Naples, and De- 

 cember 2nd has the following record : 



