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True Apparent Places of Thirty-seven of the Principal Fixed Stars, for every tenth day of the year.

Epoch.-The Upper Culmination at Greenwich.

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Dr. Young's Refractions, the Barometer being at 30 inches, and the internal Thermometer at 50, or the external at 47, degrees; with the corrections for one inch in the barometer, and for - one degree in the thermometer of Fahrenheit. From page 19 of Vol. 1st of Pearson's Practical

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4,4

4,2

4,0

3,9

50 25.43 55 5,1 55 25. 3 53 4,9 1. 024.25 52 4,7 523.43 50 4,6 10 23.13 49 4,5 15 22.40 48 20 22. 8 46 25 21.37 45 30 21. 7 44 35 20.33 43 3,8 40 20.10 42 3,6 45 19.43 40 3,5 50 19.17 39 3,4 55 18.52 39 3,3 2. 0 18.29 38 3,2 5 18.5 37 3,1 10 17.43 36 3,0 15 17.21 36 2,9 2017. 0 35 2,8 25 16.40 34 2,8

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40 3.39,2 7,34,448 50 3.36,7 7,26,444 9. 05.54 11,9,76 15. 03.34,3 7,18,439 105.47 11,7,74 30 3.27,3 6,95,424 205.41 11,5,73 16. 03.20,6 6,73,411 11,3,72 30 3.14,4 6,51,399 11,1,71 17. 03. 8,5 6,31,386 11,0,70

30 5.36

303. 2,96,12,374

4.

011.52 24,1 1,70 10 11.30 23,4 1,64

10. 05.20

10,9,69 18. 02.57,6 5,94,362

105.15

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2011.10 22,7 1,58

20 5.10

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30 10.50 22,0 1,53

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40 10.32 21,3 1,48

405. 0

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50 10.15 20,7 1,43

50 4.56

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45,4 1,52,090 65 27,2,91,055 77 13,4,45,027 89 43,8 1,47,088 66 25,9,87,052 78 12,3,41,025 90 54 42,2 1,41,085 67 24,7,83 ,050|| 79 | 11,2,38,023

1,0,03,002 0,0,00,000

The correction for an increase of altitude of one inch in the barometer, or for a depression of one degree in the thermometer, is to be added to the tabular refraction; but when the barometer is lower than 30 inches, or the thermometer higher than 47 degrees, the correction becomes subtractive.

When great accuracy is required, 0,003 inch should be deducted from the observed height of the barometer, for each degree that the thermometer near it is above 50 degrees, and the same quantity added for an equal depression.

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A second of time, at the Equator, contains 1521 feet.

II. METEOROLOGICAL INFORMATION.

I. METEOROLOGICAL TABLES FOR CAMBRIDGE, MASS. Summary of the Meteorological Observations made at the Observatory of Harvard College. By W. Cranch Bond. North Lat. 42° 22. Lon. West of Greenwich, 71° 07'. From May 1st, 1843, to May 1st, 1844.

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May,

June,

29.941 29 960 29.920.040 29.956 29.944 46.8 56.1 64.6 50.5 54.5 29.888 29.868 29.852.016 29.875 29.871 55.2 67.3 73.461.164.2 July, 29.919 29.919 29.876.043 29.908 29.905 61.1 71.2 78.7 65.8 69.2 August, 30.007 29.99829.990.008 30.003 29.999 63.6 71.1 78.566.569.9 September, 30.047 30.043 30.010.033 30.033 30.033 54.2 61.069.2 57.960.6 October, 29.870 29.872 29.806.066 29.833 29.845 41.8 46.5 54.7 46.1 47.3 November, 30.034 30.041 29.987.054 29.960 30.005 29.6 34.2 40.9 32.6 34.3 December, 29.989 29.966 29.915.051 29.926 29.949 23.8 26.0 32.7 25.0 26.9

1844. January, 29.948 29.895 29.891.004 29.976 29.928 10.7 14.4 21.2 15.1 15.3 February, 30.015 30.005 29.963.042 30.003 29.996 17.4 23.7 33.1 24.0 24.6 29.982 30.012 30.005.007 29.995 29.999 29.5 34.0 39.1 32.5 33.830.168 30.154 30.097.057 30.120 30.135 39.5 49.1 60.244.848.4 29.984 29.978 29.943 .035 29.966 29.968 39.4 46.253.943.545.8

March,

April,

Mean,

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August,

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1.3

1.1

September, 1.3 1.4 1.5 1.0
October, 1.3 1.4 1.6
November, 1.5 1.2 1.5 0.7 1.2 4.0 5.6
December, 1.3 1.2 1.4 1.3 1.3 6.3 6.6
1844.

4.6 4.8 4.2 4.0

January, 1.4 1.4 1.7 1.5 1.5
February, 1.3 1.2 1.4 0.9 1.2 4.5 5.0 5.0 5.3
March, 1.6 1.6 1.8 1.2 1.5 6.1 5.9
April,

Mean,

4.95 2.033 7.3 7.0 6.58 5.844 1.1 1.3 1.4 1.1 1.2 5.0 5.3 4.6 4.9 4.95 0.342 1.33 1.30 1.60 1.11 1.33,5 .06 5.08 5.31 5.00 5.11 46.140

4.3 4.1

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1.4 5.3 4.9

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4.40 4.294

*The figures in this column express the difference between the two preceding columns.

The greatest range of the barometer, in 24 hours, was on the 12th and 13th of February, 1.260 inches.

The barometer was

Lowest, February 13th, at 9 A. M.-29.044,-attached thermometer, 50° Highest, April 2d, at 9, A. M.,―30.826,

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35°

The mean height of the barometric column, at the hours specified above, during the year, was 29.968; its cistern being 44 feet above the mean level of high water, Charles River, at Brighton Bridge.

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The external thermometer, Fahrenheit's scale, has entire exposure on the north side of the building; the sun never shines directly upon it, and it is affected by reflected heat only occasionally, at the 3 P. M. observation, and this probably to a small amount; it is fixed on a bracket projecting six inches from the wall, and is six feet above the surface of the ground. The barometric observations have been corrected for capillary action, and reduced to the temperature of 32° Fahrenheit, but not for elevation. The rain gauge is a cubical box of zinc, 10 inches by the side, and rests on the surface of the ground.

The hours of observation adopted in these tables, are those generally used by observers in England. The mode of notation for the winds and clouds also deserves notice. In the former case, 0 denotes a perfect calm, and 6 the greatest violence of the wind. In the latter case, o denotes a sky without any clouds, and 10 a sky completely overcast. As uniformity in these tables is very desirable, it is to be wished that this method should be adopted by observers throughout the country.

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