Part 7

+------++-----------------------------------++-------------+ | || SELF-REGISTERING THERMOMETER. ||PLUVIOMETER. | | || || | | ||---------+-----+-----+-------+-----||------+------| | || | | | | || | | | ||Absolute | | | Mean | || Rain | | |1849. || | Mean| Mean|Monthly|Range|| and | Snow.| | ||---------| of | of |Temper-| || Snow.| | | ||Max.|Min.| Max.| Min.| ature.| || | | | || | | | | | || | | |------||----+----+-----+-----+-------+-----||------+------| | || ° | ° | ° | ° | ° | ° ||Inches|Inches| |Jan. ||50· |18·7|42·14|35·82| 38·987| 31·3|| 5·683| | |Feb. ||51· |30· |45·91|40·07| 42·990| 21· || 2·045| | |March ||54· |28· |46·79|39·96| 43·375| 26· || ·837| | |April ||62· |29· |49·73|38·51| 44·124| 33· || 1·488| ·090 | |May ||70· |36·5|60·51|45·85| 53·185| 33·5|| 3·037| | |June ||67·5|40·5|61·53|48·55| 55·044| 27· || 1·224| | |July ||75·5|46· |63·93|53·74| 58·835| 29·5|| 5·478| | |Aug. ||72· |46·5|64·05|55·03| 59·541| 25·5|| 3·771| | |Sept. ||74· |42·5|62·56|50·48| 56·524| 31·5|| 2·814| | |Oct. ||64· |34· |52·16|43·11| 47·636| 30· || 5·252| | |Nov. ||55· |27·7|47·85|42·77| 45·310| 27·3|| 4·974| | |Dec. ||52·5|25· |41·69|35·93| 38·810| 27·5|| 2·396| | |------||----+----+-----+-----+-------+-----++------+------| |Means ||62·3|33·7|53·24|44·15| 48·696| 56·8||38·999| ·090 | | || | | | | | || | | +------++----+----+-----+-----+-------+-----++------+------+

+------++-------------------------------------+ | || | | || | | || | | || | | || | | || | | || Wet |Evapor-| Prevailing ||Force| | ||Days.| ation | Winds. Two || of | |1849. || | Gauge.| Daily ||Wind,| | || | | Observations. || 0-5.| | || | | || | | || | | || | |------||-----+-------+----------------++-----| | || | Inches| || | |Jan. || 20 | ·909 |SW. || 3·2 | |Feb. || 12 | 1·024 |SW. || 2·1 | |March || 13 | 1·558 |SW. & NW. || 2·1 | |April || 16 | 2·620 |Easterly. || 2·5 | |May || 14 | 3·886 |SW. || 2·0 | |June || 10 | 5·076 |SW. || 1·9 | |July || 18 | 4·156 |NW. || 2·3 | |Aug. || 19 | 2·657 |SW. || 1·4 | |Sept. || 12 | 3·337 |E., Variable 1·5|| | |Oct. || 17 | 1·723 |SW. || 2·3 | |Nov. || 24 | ·960 |SW. || 2·4 | |Dec. || 15 | ·793 |E., Variable || 1·8 | |------||-----+-------+----------------++-----| |Means || 190 |28·699 |SW. || 2·1 | | || | | || | +------++-----+-------+----------------++-----+

HYGROMETER.

+---------++----------------------------------++ | || At 3h P.M. || | || || | ++-------+-------+----------+-------++ | || | | | || | 1849. || Mean | Mean | Mean | Com- || | || of | of | Dew- |plete- || | || Dry | Wet | Point |ment of|| | || Bulb. | Bulb. | De- | Dew- || | || | |duced.[25]|Point. || | || | | | || +---------++-------+-------+----------+-------++ | || ° | ° | ° | ° || |January || 40·28 | 39·02 | 36·68 | 3·60 || |February || 44·66 | 42·50 | 40·08 | 4·46 || |March || 45·85 | 43·17 | 40·02 | 5·82 || |April || 48·66 | 43·94 | 39·13 | 9·53 || |May || 58·79 | 52·85 | 48·39 | 10·40 || |June || 60·23 | 53·44 | 48·68 | 11·54 || |July || 63·13 | 57·47 | 53·82 | 9·30 || |August || 62·43 | 57·77 | 54·59 | 7·84 || |Sept. || 61·95 | 56·48 | 52·87 | 9·08 || |October || 51·17 | 48·13 | 45·09 | 6·06 || |November || 46·65 | 45·10 | 43·23 | 3·41 || |December || 40·25 | 38·74 | 36·40 | 3·79 || +---------++-------+-------+----------+-------++ |Means, || 52·00 | 48·21 | 44·91 | 7·07 || |1848, || 51·93 | 48·23 | 44·98 | 6·95 || |1847, || 51·94 | | 44·12 | 7·82 || +---------++-------+-------+----------+-------++

+---------++---------------++---------+-------+ | || WEIGHT OF || | | | || VAPOUR. || | | | ++-------+-------++ Degree | | | || |Requir-|| of |Weight | | 1849. || In a |ed for ||Humidity,| of a | | || Cubic | Satu- ||(complete| Cubic | | || foot |ration || Satu- |foot of| | || of | of a || ration | Air. | | || Air. |Cubic || =1·000).| | | || | foot. || | | +---------++-------+-------++---------+-------+ | ||Grains.|Grains.|| |Grains.| |January || 2·80 | 0·32 || 0·899 | 546·2 | |February || 3·04 | 0·57 || 0·844 | 546·8 | |March || 3·03 | 0·72 || 0·811 | 543·7 | |April || 2·87 | 1·23 || 0·701 | 535·1 | |May || 3·93 | 1·73 || 0·696 | 527·2 | |June || 3·91 | 1·99 || 0·663 | 527·8 | |July || 4·70 | 1·77 || 0·726 | 522·6 | |August || 4·85 | 1·50 || 0·767 | 523·2 | |Sept. || 4·55 | 1·71 || 0·728 | 523·7 | |October || 3·58 | 0·87 || 0·804 | 533·8 | |November || 3·41 | 0·43 || 0·888 | 538·8 | |December || 2·71 | 0·41 || 0·878 | 548·1 | +---------++-------+-------++---------+-------+ |Means, || 3·61 | 1·10 || 0·784 | 534·7 | |1848, || | || | | |1847, || | || | | +---------++-------+-------++---------+-------+

Footnote 25: From Mr Glaisher's Hygrometrical Tables, the accuracy of which my own series of observations made in the years 1847 and 1848, for the purpose of testing their correctness, shew in a very striking manner; and I think every meteorologist must feel himself greatly indebted to Mr Glaisher for this valuable compilation, which is also based on observations made under his own superintendence at the National Observatory.

In eight months of the year 1847, the difference between the observed and the deduced Dew-point at Whitehaven, is 0°·10; and in 1848, it is only 0°·07, the mean of the two periods comprising 1220 observations, amounting to the comparatively evanescent fraction of 8/100ths of a degree. Such satisfactory proofs of the perfection of Mr G.'s tables have induced me to abandon Daniell's Dew-point Apparatus, for that more simple, less costly, and equally correct form of Hygrometer, the combination of the dry and wet bulb thermometers.

SOLAR AND TERRESTRIAL RADIATION.

[Transcriber's Note: Key to abbreviations in table headers: Six's = Six's Thermometer, 4 feet above Ground; O G = On Grass; O W = On Wool.]

+-----------------------------------------------------------+ | || ABSOLUTE MINIMA.||MEAN NOCTURNAL TEMPERATURE.|| | ||----------------------------------------------|| | 1849. ||Six's| On | O W ||Six's| Naked Thermometers || | || |Grass| O G || | O G |O W O G| Diff. || |----------||-----+-----+-----||-----+-----+-------+-------|| | || ° | ° | ° || ° | ° | ° | ° || |January, || 18·7| 4· |--2·8||35·82|30·35| 27·71 | 2·64 || |February, || 30· | 20·5| 18· ||40·07|35·38| 33·08 | 2·30 || |March, || 28· | 19·5| 14·7||39·96|34·88| 32·60 | 2·28 || |April, || 29· | 21·3| 16· ||38·51|32·72| 28·88 | 3·84 || |May, || 36·5| 26· | 22· ||45·85|39·27| 36·27 | 3·00 || |June, || 40·5| 29·5| 25· ||48·55|41·06| 37·86 | 3·20 || |July, || 46· | 33· | 29· ||53·74|45·52| 42·43 | 3·09 || |August, || 46·5| 35· | 31·5||55·03|49·25| 46·05 | 3·20 || |September,|| 42·5| 31·8| 28· ||50·48|42·84| 39·53 | 3·31 || |October, || 34· | 24·5| 18·5||43·11|37·15| 33·46 | 3·69 || |November, || 27·7| 19·5| 14·5||42·77|37·79| 35·72 | 2·07 || |December, || 25· | 17·5| 11·5||35·93|30·29| 27·08 | 3·21 || |----------||-----+-----+-----||-----+-----+-------+-------|| | 1849, || 33·7| 23·5| 18·8||44·15|38·04| 35·05 | 2·98 || | 1848, || 32·5| | 20·2||43·79| | 35·73 | || | 1847, || 33·7| | 20·5||43·50| | 35·95 | || | 1846, || 36·1| | 23·1|| | | | || +-----------------------------------------------------------+

+--------------------------------------------------------------------------+ | || TERRESTRIAL RADIATION. | | ||--------------------------------------------------------------| | 1849. || Maximum. || Minimum. || Mean. | | || O G |O W O G| || O G |O W O G| Day. ||O G |O W O G| |----------||-----+-------+---------||-----+-------+---------||----+-------| | || ° | ° | || ° | ° | || ° | | |January, || 14·7| 21·5 | 3d || 1· | 1·5 | 7th||5·47| 8·11 | |February, || 11·5| 13· | 17th|| 1·5 | 1·5 | 3, 22d||4·69| 6·99 | |March, || 14·5| 16· | 31st|| 0· | 1·5 | 11,12th||5·08| 7·36 | |April, || 11·5| 17·5 | 11th|| 3· | 3· | 3d ||5·79| 9·63 | |May, || 12· | 17·5 | 1st|| 1·5 | 2·5 | 15th||6·58| 9·58 | |June, || 14· | 19·5 | 4th|| 2· | 3·5 | 26th||7·49| 10·69 | |July, || 16· | 20· | 16, 17th|| 3· | 4· | 4th||8·22| 11·31 | |August, || 19· | 22· | 4th|| 2· | 3· | 26th||5·78| 8·98 | |September,|| 13· | 18·5 | 27th|| 2· | 2·5 | 16, 20th||7·64| 10·95 | |October, || 14· | 21· | 17th|| 0· | 1· | 25, 30th||5·96| 9·65 | |November, || 10·5| 13·2 | 24, 28th|| 1·5 | 1·5 | 8th||4·98| 7·05 | |December, || 17·5| 21· | 4th|| 0· | 0·5 | 8th||5·64| 8·85 | |----------||-----+-------+---------||-----+-------+---------||----|-------| | 1849, || 14·0| 18·4 | || 1·46| 2·16 | ||6·11| 9·09 | | 1848, || | 15·9 | || | 1·94 | || | 8·06 | | 1847, || | 15·1 | || | 1·14 | ||[26]| 7·45 | | 1846, || | 14·6 | || | 1·35 | ||[27]| 7·45 | +--------------------------------------------------------------------------+

+---------------------------------+ | || IN SUN'S RAYS. | | ||---------------------| | 1849. || Max. |Mean.|Solar | | || | |Rad.[28]| |----------||------|-----|--------| | || ° | ° | ° | |January, || 59 | 45·5| 3·37 | |February, || 67 | 54·4| 8·49 | |March, || 77 | 61·3| 14·51 | |April, || 93 | 69·3| 19·57 | |May, || 133 | 88·0| 27·49 | |June, || 106 | 89·2| 27·67 | |July, || 106 | 96·3| 32·37 | |August, || 104 | 85·8| 21·75 | |September,|| 102 | 81·1| 18·54 | |October, || 75 | 64·9| 12·74 | |November, || 67 | 50·9| 3·05 | |December, || 56 | 44·1| 2·41 | |----------||------+-----+--------| | 1849, || 87·0 | 69·2| 15·99 | | 1848, || | | | | 1847, || 90·2 | 71·0| 17·15 | | 1846, || | | | +---------------------------------+

Footnote 26: In 1847, the Thermometer was on Cork throughout the year. It is here reduced to the Standard of Raw Wool.

Footnote 27: In 1846, the Thermometer was placed on Cork in cloudy and wet weather. The results are reduced to the Standard of Raw Wool, by adding 0°·25 to the _recorded_ annual mean.

Footnote 28: Difference between the mean maximum in the Sun's rays, and the mean maximum in the shade.

_Form, &c. of Instruments._

The Barometer (the frame of which is brass) is a standard made by Barrow, under the direction of James Glaisher, Esq., of the Greenwich Observatory.

The adjustment for the difference of capacity of tube and cistern is effected previous to every observation, and the correction for capillarity and reduction to the temperature of 32° is made at the close of each month.

The difference between its readings and those of the Greenwich standard is scarcely appreciable, being only 0·002 inch.

The Dry and Wet Bulb Thermometers, also made by Barrow, are considered to have identical readings under similar circumstances, and both, too, agree with the Greenwich standard thermometer. The Dew-point apparatus, now discontinued, approximates very closely in its readings to the dry and wet bulb thermometers.

The Self-registering Thermometer is a large Six made by Dollond in 1840, and its average difference from the standard is within 2/10ths of a degree. A duplicate and precisely similar thermometer (which has also been repeatedly compared with a standard at every part of the scale) is fixed by its side, so that in case of No. 1 getting out of order, No. 2 can be resorted to without detriment to the results.

These instruments all have a northern aspect, and are placed about 4 feet above the ground. The naked thermometers employed for indicating the relative amount of solar and terrestrial radiation, are precisely similar to those in use at the Government Observatories.

The Rain and Evaporation Gauges are 8 inches in diameter, and the metres are graduated to the 1/1000th part of an inch. Both are read off daily. The aperture of the rain-gauge is about 7 feet above the ground. The evaporation dish is mounted on a moveable stand, 4 feet 4 inches in height, and the circular shelf on which the vessel rests, is just large enough to hold it. The gauge receives a fair proportion of wind and sunshine, and is always exposed in the open air during the day, except when _rain is falling_. At night and in wet weather, it is placed under a capacious shed, 9 feet in height, and open in front. Thus, it is conceived that the evaporating surface is freely acted upon by all the circumstances concerned in promoting this important natural process.

The direction of the wind is taken twice daily, and its force is registered on an arbitrary scale from 0 to 6; the highest number is reserved for storms approaching the hurricane in violence, and is very rarely recorded.

_Remarks on the Weather in 1849._

_January._--A damp wet month, except the first week, when sharp frost prevailed. The mean temperature is 0°·68 _above_ the average. On the night between the 2d and 3d, a naked thermometer on the grass fell to 4°, and one on raw wool to 2°·8 below zero, being the lowest temperature I have recorded. The radiation indicated by raw wool was 21°·5. Between one and two o'clock on the morning of the 10th, a terrific thunder-storm burst suddenly over the town, and spread great alarm amongst the slumbering inhabitants. Seven or eight dazzling discharges of the electric fluid, followed by deafening crashes, succeeded each other in about as many minutes. The storm was almost vertical; and between several of the flashes and the accompanying thunder, there was scarcely an appreciable interval, certainly not more than a single second of time. The war of the elements ceased as suddenly as it commenced, and altogether, the storm did not last more than ten minutes. The wind, which previously blew a heavy gale, lulled almost to a calm as the last peal died away. The storm was followed by a heavy fall of rain and hail. It appears to have been pretty much confined to this town and neighbourhood. Thunder was also heard on the evening of the 14th, and lightning was seen on the nights of the 21st, 26th, and 29th. Saturn's ring was perceived at this Observatory on the night of the 31st, after a long continuance of damp, wet weather. As this singular appendage was readily seen, and was well and sharply defined, I have no doubt the instrument would have shewn it ten or fourteen days earlier, had the nights been at all favourable. The ring was also seen on the night of the 11th of September 1848, during its temporary reappearance.

_February._--A fine, dry, and mild month. The temperature 3°·49 _above_ the average of twelve years. On the 11th, the barometer attained the remarkably high point of 30·82 at this Observatory, which is about 90 feet above the sea level. At the Royal Observatory, Greenwich (40 feet above sea), the maximum was 30·85, being greater than any reading since January 1825, when the barometer at the Royal Society's apartments attained to 30·841, at 81 feet above the sea level; and there is no other instance recorded in the Philosophical Transactions of a reading so high as 30·8, from the commencement of the series in 1774. The maxima of pressure recorded on the 11th in various parts of the country, were all found to give a reading of 30·90 at the mean sea level.

On the 18th, primroses were in flower on the cliffs between Panton and Harrington.

_March._--Similar to February. Temperature 2°·29 _above_ the average, and the complement of the dew-point 2°·40 _below_ the mean of the two preceding years.

FIRST QUARTER.--The temperature of the first quarter of 1849 is 2°·16 _above_ the average of twelve years, and the complement of the dew-point is 1°·52 _below_ that of the corresponding quarter in the unhealthy years 1847 and 1848.

The average fall of rain is 11·593 inches; in 1849, we have had 8·565, or 3·02 inches _below_ the usual quantity.

The deaths in the quarter ending March 31, in the town and suburb of Preston Quarter, are 168, being 16 _above_ the corrected quarterly average, which is 152. In the corresponding quarters of 1848 and 1849, the deaths were 250 and 187 respectively.

The deaths exceed the births by 25 in number.

_April._--A fine, dry, but cold month. The temperature 1°·95 below the average. On the 23d the cuckoo was heard, and on the following day the swallow was seen in this neighbourhood. On Good Friday, the 6th, two parhelia, accompanied by a halo, were seen by a friend who was fishing by the river Calder. The sky was covered with a thin cirro-stratus, so that the images did not present any defined outline or disc, but consisted of three circular patches of light of nearly equal intensity, so much so, that it was difficult to distinguish the real from the phantom suns. The phenomena were first noticed about 5 P.M., and they remained visible till near six. The ring or halo passed through the centres of the parhelia, one of which was to the left, and the other to the right of the sun, with which they formed a straight line.

_May._--A fine month, with an average mean temperature. The sun shone out on 29 days. The depth of rain is about an inch _above_ the average quantity.

_June._--A very dry month, and by far the coldest June I have recorded in the last seventeen years. The mean temperature is no less than 3°·67 below the average. The hay harvest began in this neighbourhood about the 20th.

The thermometer on the grass, on raw wool, was below the freezing point on eight nights; on the nights of the 8th and 10th it fell to 27°·5, and on that of the 19th and 20th, to 25°. On several mornings ice was seen in the immediate vicinity of the town, and on the 3d of the month there was a somewhat heavy fall of snow amongst the mountains. Highbell, Kentmere, High Street, and the mountains around Mardale, were covered with the mantle of winter to the depth of 6 inches. Such an incident has not occurred, it is said, since 1827, when several sheep were lost and smothered in snow-drifts on Mosedale and Helvellyn; and Skiddaw was covered with snow. Both snow and hail are recorded on the 10th in the register kept for me at Bassenthwaite Halls, at the foot of Skiddaw.

What is most remarkable, this unusual coldness does not appear to have been experienced at all in the southern counties of England. At Greenwich, the temperature is stated to be of the same value as that of the average from 70 years, but less than that of the preceding eight years, by 1°·9. According to Mr Glaisher's tables, published in the Registrar-General's Report for the June quarter, the mean temperature in Cornwall and Devonshire _exceeds_ that of the corresponding month in 1847, by 0°·7, and south of lat. 52°, it is in excess 9/10ths of a degree. Between the parallels 52° and 53°, the temperature is 1°·2 _below_ that of June 1847; between 53° and 54°, it is 2°·1, and at Whitehaven, in lat. 54½°, it is 2°·7 below that of June 1847.

The extraordinary depression in the temperature has therefore been unparticipated in, by places situated south of the parallel of 53°.

SECOND QUARTER.--The mean temperature of the quarter ending June 30, is 1°·92 _below_ the average of twelve preceding years; and the difference between the air and dew-point temperatures is 1°·32 _above_ that of the corresponding quarter in the years 1847 and 1848.

The average fall of rain is 8·15 inches; in the second quarter of 1849, the fall is 5·74 inches, or 2·40 inches under the normal quantity.

The deaths in the town and suburb are 139, being 21 above the corrected average number, which is 117. In the June quarters of 1847 and 1848 the deaths were 177 and 147 respectively. The births exceed the deaths by 59.

_July._--Cold and wet. Temperature 1°·82 _below_ the average. The hay harvest began in this neighbourhood about the 20th June; meadow hay was rather light on the ground, but the crop generally was well secured.

_August._--Average temperature and depth of rain, with a serene and stagnant atmosphere. The complement of the dew point is 1°·78 _below_ the average of the month in the two preceding years.

_September._--A fine, mild, and rather dry month, with serene atmosphere. At the close of the month, several of the public fountains were dry, and most of the pumps in the town had ceased to yield their supplies.