METEOROLOGICAL OBSERVATIONS. 601 
The barometric observations at Olympia are of a barometer noted by G. W. Stevens as con- 
taining air, in April, 1854. They have a large zero error, and the succession of readings is often 
such as to prove that the errors of measurement are very large. The suinmaries would, there- 
fore, give no valuable data to judge of the mean position of the barometer then, or of the measures 
of variation. 
The hygrometric observations are not embraced in the summary, as they can only be pre- 
sented accurately in deduction, or in detailed observations. ‘The mean differences of the wet 
and dry bulb are very small. In August, 1854, the mean difference at sunrise is but one and a ; 
half degrees, at 2 p. m. 7.5 degrees, at 9 p. m. 3.2 degrees. In September, 1854, these differ- 
ences are, for the respective hours, 1.4, 4.3, and 1.5 degrees. These are the dryest months 
except July. It will be seen that these results differ largely from the same measures east of the 
Cascade range of mountains and at Fort Benton, and prove the coast atmosphere to contain a 
large proportion of moisture at all seasons. In the rainy months, the differences between the 
hygrometer and the dry thermometer are very small. 
Summary of Meteorological Observations at Olympia, Washington Territory. 
Thermometer. i 
Bel 
Date. S| 3 Remarks. 
7 a.m. | 2p.m.| 9 p.m. | Mean. | Maxi-| Mini-| 2 | 2 
mum, }mum.) S| 
3° ° (o) fo} ° (o} 
April, 1854...--. 44, 9 57. 1 49, 6 50.53 | 72 34.5 | 24 | 0 | Profuse and almost constant rains. Frost on 
the 8th, 11th, 21st, and 25th; wind irregu- 
lar, mainly south to west and north, and 
light. 
May, 1854....--. 48,2 63. 2 53.1 54.80 | 83 41 8 | 8 | Irregular and moderate rains. Heavy white 
frost on 13th; wiods light, and very irregular. 
June, 1854....... 54, 0 64.0 57.0 58.33 | 74.5 | 49 15 | 7 | Frequent irregular rains. Wind very variable ; 
but few clear days. 
July, 1854....... 55.0 75.9 64. 0 65. 00 | 89.4 | 45 0 | 20 | Very slight rain on 15th; winds north and 
northwest mainly, light; mostly clear from 
7th to 27th. 
August, 1854..... 55.5 74.2 65.5 65. 07 | 86.5 | 48 7 | 9/|1.83 inches of rain. Much cloudy weather ; 
winds very light and irregular. 
. 36 inches of rain. Rains and winds irregu- 
lar; generally cloudy. 
October, 1854....| 45.3 60.2 48.7 51.40 | 73 38 13 | 6 | 3.14 inches of rain; rains nearly continuous 
from the 20th; winds south and southeast. 
Heavy frost on 6th, 7th, 8th, and 9th, and 
on 12th and 13th. 
November, 1854.-| 43.0 51.9 45.5 46.80 | 67 32 12 | 33.91 inches of rain; winds principally south 
and southwest. Rains nearly continuous 
from 17th to 24th; no snow. 
December, 1854.-| 39.7 46.0 42.0 42.57 | 58 31 15 | 311.32 inches rain; rains nearly continuous 
: from 20th. <A little snow on 26th; winds 
south and southwest. 
January, 1855....| 38.9 45.7 40.4 41.67 | 57 26 18 | 2 16.62 inches of rain. Three days snow, six 
inches in depth on 4th; winds south or 
southward during rains and snows. 
February, 1855*..| 41.0 49.7 44,3 45.00 | 62 34.5 9) O | Amount of rain not measured. First part of 
month generally cloudy and rainy. 
_ 
September, 1854.) 53.1 69. 0 56.9 59. 67 | 84.5 | 45 6 
a 
* Observations to 17th only. 
