Dr. Heiiieken's Meteorological Register kept at Funchal. 363 



tion ; and because the instrument challenges and deserves 

 every attention — an observation after sun-set was for at least 

 nme months in twelve incompatible with health, and one at 

 noon or a few hours later would necessarily have been so 

 often interrupted, that it would have been an incumbrance 

 rather than otherwise. During many of our heavy rains it 

 (the hygrometer) has shown several degrees of dryness, but 

 this has invariably occurred with the wind at N. or N. W. ; at 

 S. or S.W. it has seldom reached a degree before deposition 

 has taken place; and this apparent discrepancy is, I think, 

 fully accounted for, by supposing that as the former (the N. 

 and N.W. rains) originate upon, and come to us from, the 

 mountains ; w-e are drenched by rains which belong (if I may 

 be allowed the term) to those regions, our own immediate at- 

 viosphcre remaining for a time at least below the point of satu- 

 ration. Throughout the year 1826 the sirocco visited us 

 seldom, and then was generally either incomplete in its cha- 

 racter or partial in its influence ; but in a former year the 

 hygrometer during its prevalence once showed 45 degrees of 

 dr^'uess, and even then fether failed to produce a deposition. 

 I take for granted that it is very well established ; although I 

 am ignorant of the explanation, why the sirocco here is so 

 perfectly dry, and that of the Mediterranean so loaded with 

 moisture. It reaches us immediately from the coast of Africa, 

 after passing over about 300 miles of sea : not a cloud is to 

 be seen during its continuance ; the whole atmosphere is of 

 one uniform unvaried blue, of a peculiar character, as though 

 viewed through what a painter would term a very thin warm 

 aerial haze; it blows from the E.S.E., lasts almost invariably 

 three days, and encounters you like the puffs from the mouth 

 of an oven or furnace; the eyes and lips feel much as they do 

 when exposed to a keen easterly wind on a frosty day in a 

 northern climate : birds and insects seem to suffer from it 

 more or less, and fowls confined in a close yard generally 

 droop. Furniture warps and cracks ; books gape as they do 

 when exposed to a fire, and it is generally inconvenient and 

 oppressive ; but I have never heard (although no precautions 

 are taken to avoid it by the labouring classes) that any ill ef- 

 fects have been produced by it. Some have asserted that it 

 has raised the thermometer as high as 130^ in the sun, and 

 95° in the shade ; but I doubt the accuracy of the observa- 

 tions: for in the course of four years I have never seen it 

 raised above 85° in perfect shade. There is, however, nolliing 

 in which observers are so likely to differ as in their results of 

 the maximum heat in the shade in this place. I do not believe 

 that i( is to be accurutchj obtained, but by a series o/'observa- 

 3 A 2 tions. 



