ON SELF-REGISTERING METEOROLOGICAL INSTRUMENTS. 111 
tenberg between 4 and 5 o'clock, and this falling lasted for one hour and 
twenty minutes. The beginning of this phenomenon was marked so pre- 
cisely by the autographs, that no uncertainty greater than five minutes could 
have occurred. 
These first trials are only intended as examples to show the method of 
using such instruments with the view of furnishing dates for the advancement 
of science. The proposed object to be effected by the hourly observations 
for thirty-six successive hours, at a fixed time, may by such instruments be 
more readily and minutely attained. It is hardly to be expected that the 
phznomena suited for such studies should exactly occur on such days as 
have been previously selected, whilst by the assistance of such instruments 
they cannot fail to be registered at all times and whenever they may occur. 
The example here furnished may suffice as a first attempt to show in what 
manner such an apparatus may be applied for the promotion of science by 
multiplying the materials fit to be studied. If they should be deemed of too 
voluminous a nature, the consideration should not be lost sight of, that such 
studies have never suffered from too great a multiplicity of useful data, but 
frequently from the contrary cause. 
Taste I. Barometric Maxima and Minima at Senftenberg and Prague, 
August 1844. 
Senftenberg. Prague, Difference. Senftenberg. Prague. Diffarenge. 
Max. | Min. | Max, | Min, |Senf.! Prag. Max. | Min. | Max, Min. Senf. Prag, 
0. 333-56) 321-68] 344-50 331-50| 6°88) 1-00 Oct. 7.| 391-47] 316-76 381-23] 387-01) 471 | 429 
. | 321-88] 319-44| 331-95 328-71) 2-44! 3-24)| ,, 8. | 821-61] 319-07, 331-71/ 329-88) 2:54) 1:83 
. | 319-28] 317-66] 328-90, 327-61] 1-62 1-29] ,, 11.| 321-32) 317-86 331-41) 327-21] 3:46 | 4:20 
. | 319-33] 315-24| 328-54| 325-05] 4-03) 8-49] ,, 12, | 322-14] 320-34| 332-27| 330-80] 1:80 | 1-47 
. | 318-25) 315-47| 328-37 325-78] 2-78, 2-59)| ,, 15,| 318-42) 315-69) 328-23) 325:33) 2-738 | 2:90 
6. | 318-79] 315-72) 328-92 326-70) 3-07| 2:22) ,, 20, | 320-15] 316-05) 330-16) 25:56, 4:10} 4-60 
. | 319-48] 317-75] 329-33| 328-00) 1-73) 1:33] ,, 29, | 322-16] 319-62 332-47/ 3830-16} 254 | 231 
. | 321-69] 319-24] 332-29 329-00) 2-45| 3:29] Noy. 1.| 321-96] 318-71 332-14) 328-49) 3:25 | 3°65 
. | 319-00] 318-64] 329-40 328-59/0°36| 0-81] ,, 2, 318-58] 315-62! 828:31/325-18] 2-96 | 313 
3. | 321-06) 317°34| 330-79) 328-09 3:72)2-70) ,, 3, | 815-53) 313-95, 325-69) 323-62/ 1:62 | 2-07 
9.| 319-34] 317-76| 329-60 32873] 1-58/0:87| ,, 8. | 319-02] 316-30 329-17) 325-48) 2-72 | 369 
1. | 319-09} 317-50) 329-75| 326-95) 1:59 2-80) ,, 9, | 316-21} 314-42 325:33/324-42) 1:79 | 0-91 
4,| 318-15] 316:21| 328-71} 325°80| 1:94/2:91 ,, 9,|316-34) 314-42 326-04| 324-42; 1:92] 1-62 
6. | 318-06] 315-63) 328-91) 325-72) 2-43 3-19] ,, 10,| 318-13) 316-25 327-33, 326-42) 1°88 | 9-91 
2. | 319-90| 318-94) 329-51 328-69] 0-96|0-82| ,, 14.|322-92/ 317-75 333-69|327°88| 5°17] 5°81 
. | 321-09] 318-62) 331-10' 328-72] 2°47/2:38| ,, 15.| 825-08] 328-04 335-84] 33386] 2-02 | 1-98 
8. | 324-04! 321-82| 333-99) 331-35] 2-22, 2°64) ,, 15,| 3825-08] 323-09, 335-84|332-49| 1:99 | 3:35 
. | 821-71| 320-00) 331-25) 329-67] 1-71) 1-58!) ,, 16,| 322-66) 320-73 332°31/ 331-64) 1:93 | 0-67 
0. | 32306) 319-60) 334-05) 329-70| 3-46, 4°35) ,, 16, | 322-76) 320-73, 333-96 331-64, 2°03 | 2-32 
1, | 323-68] 321-89] 334-25| 331-87| 1-79, 2°38) ,, 17./324:36 322°97) 335-06 33413] 1:39 | 0-938 
4 | 
2. | 321-77| 316-49] 331-69) 326-17) 5°28, 5°42| ,, 20.|324-27| 322-13 334-72, 332-47) 2-14 | 2-25 
8. | 317-81] 315-49) 328:51|326-00| 2:32, 2-51) ,, 21.|321-84) 318-59| 332-23/ 329-60) 3:25 | 2-63 
4, | 321-22) 315-30) 331-78] 826-04) 5-92) 5-74) Dec, 30, | 323-43) 320-95) 333-54) 380-94) 2-48 | 2-60 
5. | 322-28) 320-74! 332-23| 330-32) 1-54) 1-91 Sum! 119-91 | 122-58 
oe 320-49| 331-42| 330°35| 1-20) 1-07 Mean .| 2498| 2-554 
3 
