498 
THE  AHMIEALTY  ASTEOXOmCAL  EXPEEDIEXT 
Obtaining,  however,  the  ratio  of  the  true  radiation  of  August  4,  and  the  wind-lowered 
radiation  of  August  1,  during  the  period  common  to  both,  and  applying  it  throughout, 
we  have  for  the  latter  day  the  following  tabular  -view  of  the  progress  of  radiation  -f-  and 
— through  the  twenty-four  hours,  at  the  height  of  8903  feet  above  the  sea-level. 
Radiation  at  Guajara  on  August  1,  con'ected. 
Date. 
Radiation. 
Temp. 
Date. 
Radiation. 
Temp. 
Date. 
Radiation. 
Temp. 
h 
m 
O 
h 
m 
h 
m 
C 
Aug.  1 
4 
43  A.M. 
- 5-8 
47 
Aug.  1.  1 
13 
P.M. 
+ 123-4 
60 
Aug.  1. 
9 
43 
P.M. 
- 6-3 
49 
4 
58  A.M. 
- 5-6 
47 
1 
28 
P.M. 
119-4 
61 
9 
58 
P.M. 
6-1 
50 
At  5h 
10'" 
Sunrise 
1 
43 
P.M. 
123-1 
6l 
10 
13 
P.M. 
6-7 
50 
5 
13  A.M. 
- 3*0 
47 
1 
58 
P.M. 
123-4 
60 
10 
28 
P.M. 
5-8 
49 
5 
28  A.M. 
+ 7-0 
47 
2 
13 
P.M. 
119-2 
60 
10 
43 
P.M. 
6-3 
49 
5 
43  A.M. 
30*5 
48 
2 
28 
P.M. 
121-2 
60 
10 
58 
P.M. 
6-4 
49 
5 
58  A.M. 
49-0 
48 
2 
43 
P.M. 
116-7 
59 
11 
13 
P.M. 
6-0 
48 
6 
13  A.M. 
63-0 
49 
2 
58 
P.M. 
112-3 
60 
11 
28 
P.M. 
6-0 
48 
6 
28  A.M. 
73-0 
49 
3 
13 
P.iM. 
112-3 
59 
11 
43 
P.M. 
6-4 
48 
6 
43  A.M. 
81-0 
50 
3 
28 
P.M. 
110-7 
59 
11 
58 
P.M. 
6-1 
48 
6 
58  A.M. 
88-0 
50 
3 
43 
P.M. 
112-6 
58 
Aug.  2. 
0 
13 
A.M. 
6-0 
48 
7 
13  A.M. 
96-5 
51 
3 
58 
P.M. 
109-5 
59 
0 
28 
A.M. 
5-7 
48 
7 
28  A.M. 
99-0 
51 
4 
13 
P.M. 
108-9 
58 
0 
43 
A..M. 
4-7 
48 
7 
43  A.M. 
101-0 
52 
4 
28 
P.M. 
103-2 
58 
0 
58 
A.M. 
5-7 
48 
7 
58  A.M. 
103-0 
52 
4 
43 
P.M. 
98-1 
57 
1 
13 
A.M. 
5-7 
48 
8 
13  A.M. 
106-5 
53 
4 
58 
P.M. 
93-6 
56 
1 
28 
A..M. 
5-5 
48 
8 
28  A.M. 
109-0 
54 
5 
13 
P.M. 
104-8 
56 
1 
43 
A.M. 
0^ 
48 
8 
43  A.M. 
113-0 
54 
5 
28 
P.M. 
104-7 
55 
1 
58 
A.M. 
6-6 
48 
8 
58  A.M. 
116-1 
55 
5 
43 
P.M. 
100-0 
55 
2 
13 
A.M. 
5-4 
48 
9 
1 3 A.M. 
117-5 
55 
5 
58 
P.M. 
93-0 
54 
2 
28 
A.M. 
8-9 
48 
9 
28  A.M. 
119-0 
56 
6 
13 
P.M. 
70-6 
54 
2 
43 
A.M. 
5-8 
48 
9 
43  A.M. 
121-0 
56 
6 
28 
P.M. 
46-9 
53 
2 
58 
A.M. 
5-8 
48 
9 
58  A.M. 
124-2 
57 
6 
43 
P.M. 
15-9 
53 
3 
13 
A.M. 
5-2 
48 
10 
13  A.M. 
125-2 
57 
At  6’'  49*^ 
Sl 
nset 
3 
28 
A.M. 
5-1 
48 
10 
28  A.M. 
121-2 
58 
6 
58 
P.M. 
+ 3-7 
52 
3 
43 
A.M. 
4-3 
48 
10 
43  A.M. 
120-0 
59 
7 
13 
P.M. 
— 1-5 
51 
3 
58 
A..M. 
4-5 
48 
10 
58  A.M. 
124-0 
59 
7 
28 
P.M. 
3-9 
51 
4 
13 
A.M. 
5-4 
48 
11 
13  A.M. 
123-9 
59 
7 
43 
P.M. 
6-7 
51 
4 
28 
A.M. 
3-7 
48 
11 
28  A.M. 
144-0 
59 
7 
58 
P.M. 
6-7 
51 
4 
43 
A.M. 
3-4 
48 
11 
43  A.M. 
152-2 
59 
8 
13 
P.M. 
6-4 
51 
4 
58 
A.M. 
3-3 
48 
11 
58  A.M. 
152-4 
60 
8 
28 
P.M. 
6-4 
50 
.At  5*' 
lim 
Sunrise 
0 
13  P.M. 
146-4 
60 
8 
43 
P.M. 
7-3 
50 
5 
13 
A.M. 
- 2-0 
47 
0 
28  P.M. 
139-8 
60 
8 
58 
P.M. 
6-3 
50 
5 
28 
A.M. 
+ 1*7 
48  ; 
0 
43  P.M. 
132-1 
60 
9 
13 
P.M. 
6-1 
50 
5 
43 
A.M. 
22-5 
48  1 
1 
0 
58  P.M. 
+ 130-2 
60 
9 
28 
P.M. 
- 6-0 
49 
5 
58 
A.M. 
+ 43-0 
48 
With  both  temperature  and  radiation  in  the  preceding  Table,  the  object  has  been 
to  exhibit  what  takes  place  on  the  most  favourable  day,  not  to  take  a mean  of  a number 
of  days,  good  and  bad ; a plan  which,  hoAvever  proper  for  the  meteorology  of  the 
mountain,  is  not  suitable  to  an  inquiry  into  the  heating  poAver  of  the  sim.  There  Avould 
have  been  advantage,  doubtless,  in  taking  a mean  of  a number  of  equally  favourable 
days,  if  they  could  be  had,  partly  to  eliminate  errors  of  obserA  ation,  partly  to  eliminate 
the  little  varying  asperities  in  the  radiation  curve,  produced  by  natural  influences: 
taking  tlie  quantities,  lioweA^er,  as  they  stand,  Ave  may  derive  from  them  some  useful 
hints  for  ulterior  proceedings ; as  thus,  that  the  next  black-bulb  thermometer  prepared 
