46 
Absolute ran^e. 
Months with 
frosts. 
Monthly range. 
Contrasts. 
Range of 
monthly means. 
to the character of the Season. It will be noted that the results 
tally very closely with that indicated hy the means of the 
decades, and, so far, confirm the correctness of the latter. 
TEMPEEATUEE 
has ranged from—4'’ on December 26th, 1860, to 89^* in Julj^, 
1873, and August, 1876, or a difference of 93°. Once besides, 
on January 3rd, 1853, it was nearly as cold,— 3J° ; and on 
December 7th, 1879, Zero was just reached, the Ouse then 
liearing for the three weeks,'December 4—24.f 
Frosts have occurred in every month except July, as June in 
’49, and August in ’73 just touched 32°. Frequently the 
minimum hovers just at 32", as if the latent heat then liberated 
caused a pause. This is specially notable in the monthly 
minima of unusually warm winters. The July minimum, 40°, 
has been repeated six times. 
The extreme range in December is 64°; in January, 665 ° ; in 
July, 49°; in November 51°. The striking change from 
November to December is due to the much lower minima of 
the latter month. It is strang'e that Zero should have been 
reached on December 7th, but no lower record than 14° for any 
year only a week earlier. There are some other unexpected 
contrasts. The lowest max. in February, 36° in ’55, is only 
6 ° above the highest minimum for the same month. In July 
’58, the max. was only 71°, whilst in ’52 and other years the 
min was 49°. For the months from November to February 
the lowest mean of the maxima are below the highest of the 
minima. For January, the former is 33‘9° (1881), and 
the latter 39*0° (1884). But in July the lowest mean max. is 
61 *6 (1854), and the highest mean min. is 54*9 (1868). 
Considering them separately, the range of monthly means is 
[* Until about 1870, the thermometers were in a shaded spot, shielded by boards, 
open towards the North. At Lawrence Street (until 1855) this appears to have 
been in the open garden. At Bootham it was near a garden wall, and within 30 
feet of the E corner of the two-storey school-rooms. About 1870, they were placed 
in a Stephenson screen near the old locality. Since this was removed, in 187b, to 
a more open spot in the garden, 90 yards from the house, the value s have agreed 
closely with those of the Y.P.S. 'fhe extreme maxima and minima used to be 
slightly lower, the latter because of there being no falling surface, down which the 
cold air slides, as at the Y.P.S. stand. The former may arise from its more open 
position. Probably the extre mes at Bootham would have been slightly greater had 
the instruments occupied a more open place.] 
f Plates IV. c& y. represent graphically most of the points considered here. 
