August 28.] 
than whole coloured ones, and require protection the first 
winter. 
8. Hybridized seed cannot he depended upon to produce 
always striped flowers ; the slips may, hut both have a 
tendency to return to the colour of the original parents. 
The seed should be sown in autumn, as soon as it is 
ripe, upon a bed previously well dug and watered, and be 
scntered thinly, and not covered with mould. If left till 
the spring following, they will be much longer in vegetating. 
I have still seeds coming up on a bed that was sown last 
year, and from which plants were successively removed. I 
mention this, that the bed in which choice seeds have been 
deposited, may not he too hastily broken up. It is a mis¬ 
take, as many suppose, that lime-rubbish or a poor soil are 
most favourable to the growth of high-coloured or striped 
flowers; my best plants grow on rich soil. Finally, the 
latest and weakliest seedlings generally produce the best 
flowers.—S. P. 
TEMrERATURE, AS INFLUENCING THE GROWTH 
OF THE WHEAT PLANT. 
By Culhbert W. Johnson, Esq., F.R.S. 
The close connexion existing between the temperature 
of a district and the successful cultivation of any particular 
crop, was an early and popular observation of both the gar¬ 
dener and the farmer. Every traveller had this knowledge 
forced, as it were, upon his attention. The intelligent gar¬ 
dener, as soon as he began to cultivate plants not indigenous 
to the soil, acted as well as he could in accordance with this 
knowledge : he placed the plants in shady places—he pro¬ 
tected them from exposure to a temperature and a degree 
of moisture foreign to their natural habits. In these latter 
times, however, the farmer has had the advantage and 
assistance of the meteorologist to guide him to similar 
conclusions—to aid him in his choice of sites and soils for 
the most successful cultivation of his crops. This knowledge 
would be both refreshing and salutary, even if it only served 
to add to the abounding interest of the natural phenomena 
of rural life, and did not directly tend to still more substan¬ 
tial benefits. The research is full of increasing interest, 
and this field of enquiry enlarges rapidly upon us as we 
proceed. To avoid, then, the temptations of deviating from 
such a portion of our subject as may be included within the 
limits of Tiie Cottage Gardener, let us strictly confine 
ourselves on this occasion to a few meteorological observa¬ 
tions on the effect of temperature upon the growth of the 
wheat plant, leaving to other opportunities a multitude of 
equally interesting and kindred enquiries. 
As I had occasion to remark in another work ( Farmers' 
Almanac, vol. v., pp. 80—54), after referring to a valuable 
prize essay by Mr. N. Whitely {Jour. It. A. S., vol. xi., p. 1), 
as a general rule, when the mean temperature of a district 
is the highest, there the corn produced is the best. The 
| mean temperature of Edinburgh is 47 ; Keswick, 40 ; 
i London, 51.0; Philadelphia, 52.5; Cairo, 78. The effect, 
then, of increase of mean heat is to improve the value of 
the corn ; but there are many causes which modify and vary 
this general rule. The great heat of a Polish or Russian 
summer, for instance, more than compensates for its short¬ 
ness. The length of the days of a northern summer, by 
giving the extra stimulus of light, also materially aids the 
rapid maturity of the crop. Amongst the retarding influences 
must be classed the elevation of the land. From the ob¬ 
servations of Schubler, in Saxony, he drew the conclusion 
that every 98.20 feet caused a delay in the harvest of wheat, 
barley, and oats, of 2.2 days. In our climate, all other 
things being the same, we think that nearly a similar rule 
of retardation is observable ; but here, again, many circum¬ 
stances cause a deviation from the rule—such as the nature 
of the soil, and more especially the subsoil, and the more 
or less rapid rate of elevation. The harvests on gravelly or 
silecious soils are much earlier, and those of clay soils much 
later, than our calculations with regard to the climate or 
elevation would justify. The harvests, for instance, on the grit¬ 
stone or moorlands of Yorkshire, at an elevation of 500 feet 
above the level of the sea, are always later than on its Chalk 
Wolds at 800 feet. We may, perhaps, take it as a general rule, 
841 
that all land in England, at an elevation of 1000 feet above 
the sea, can only be profitably employed in pastures. The 
line of extreme cultivation rises gradually as we approach 
the equator. In some of the Steppes of the Himalaya, 
barley is successfully cultivated at more than 14,000 feet 
above the level of the sea; wheat up to 12,022 feet—the j 
height of our highest mountains is only about one-third of 
this—Helvellyn is 3,055 feet; Ren Macdui, 4.148; Macgilli- 
cuddy in Ireland, 3,410. The result of Mr. Ivirwan’s obser¬ 
vations was, that in moderate rates of elevation above the i 
level of the sea, such as the rate of 6 feet per mile, for every | 
200 feet of elevation the mean annual temperature would be ; 
reduced J of a degree; that if the rate of elevation was j 
7 feet per mile, | of a degree must be allowed; if 13 feet, 
then 4-10ths of a degree; and if at the rate of 15 feet or 
upwards, then \ a degree must be allowed. In rising above 
the level of the sea, the mean temperature gradually de¬ 
creases, until at length we arrive at the line of perpetual 
snow. The following scale gives the height of the line of 
congelation in feet, and the mean temperature at the level 
of the sea, in different latitudes {Banjield and Weld’s Slat. 
Comp., p. 8) :— 
Barometer. Thermometer. Alti. in Feet. 
23.50 . 28 6,552 
19.0 46 13,044 
44.70 -'. 25 . 19,303 
0.30 . 18 20,352 
In some observations made during balloon ascents by 
Sir. Rush, it appeared that in Slay, 1837, the thermometer 
being 00° when the barometer stood at 30 inches, that the 
following changes took place during the ascent (. Athenaeum, 
1849, p. 1010):— 
hat. 
Congela. 
Temp. 
Lat. 
Congela. 
Temp. 
0 .. 
15,207 • 
50. 
5. 
15,095 . 
. 83.8 
55. 
.. 5,034 _ 
10. 
14,764 . 
. 82.6 
60. 
15. 
14,220 . 
65. 
.. 2,722 .... 
20. 
13,478 . 
. 73.1 
70 . 
.. 1,778 ... 
.. 38.1 
25. 
12,557 • 
. 74.9 
75. 
.. 1,016 _ 
.. 35.5 
30. 
1 1,484 . 
. 71.1 
80 . 
.. 0,457 
.. 33.6 
35. 
10,287 • 
. 67.0 
85. 
.. 0,117 ... 
.. 32.4 
40. 
9,001 . 
. 62.6 
90. 
45. 
7,671 . 
It would 
appear 
from some balloon 
observations of Mr 
Gay Lussac, that the temperature of the atmosphere de¬ 
creases 1° for every 352 feet of elevation. Temperature, we 
all know, materially influences the system of cultivation 
adopted even in different districts of our islands. It may 
be useful, then, if we examine the records kept in 1847 
and 1848 at three stations in corn-growing districts, viz., 
London, Thwaite in Suffolk, and Thetford in Norfolk, and 
contrast them with the register kept at Falmouth, Exeter, 
Manchester, Whitehaven, and Durham (all pasturage locali¬ 
ties), and note the mean monthly temperature of these 
places during the corn-maturing months of June, July, and 
August. The following are the results {Gardeners' Almanac, 
by G, W. Johnson ):— 
CORN 
DISTRICTS.— 
1847. 
June. 
July, 
August, 
London . 
59.5 
65.8 
63.7 
Thwaite . 
59-1 
65.9 
61.2 
Thetford. 
62.5 
72.0 
69.5 
Mean of 3 stations 
60.0 
63.6 
65.8 
London . 
1848. 
59.76 .. 
62.98 .. 
59.71 
Thwaite . 
60.37 •• 
63.97 .. 
62.39 
Thetford. 
64.5 
70.00 .. 
63.00 
Mean of 3 stations 
61.54 
65.4 
61.7 
PASTURAGE DISTRICTS.—1847. 
June. 
July. 
August. 
Falmouth . 
56.9 
61.9 
58.1 
Exeter. 
58.9 
6.3.9 
62.4 
Manchester .... 
58.4 
64.9 
60.3 
Whitehaven .... 
577 
63.2 
58.8 
Durham. 
55.7 
61.5 
56.5 
Mean of 5 stations 
57.5 
63.1 
59.2 
Falmouth . 
1848. 
57.64 .. 
60.35 .. 
57-93 
Exeter. 
58.42 
60.76 
58.76 
Manchester .... 
59.48 .. 
61.44 .. 
59.73 
Whitehaven .... 
57.56 .. 
59-87 .. 
59.87 
Durham. 
58.96 .. 
59.14 .. 
57.26 
Mean of 5 stations 
58.4 
6O.3 
57.3 
THE COTTAGE GARDENER. 
