340 
on germination of freezing the seeds just before they were ready to ger- 
minate, it was found that seeds soaked until ready to germinate and 
then kept frozen for a length of time required a longer time to com- 
plete the germination than did those that had not been frozen; the 
retardation increased in proportion to the duration of the freezing, 
amounting to about twelve days for a freezing of twenty-four days. 
The percentage of thawed-out seeds that germinated was also smaller 
in proportion as the duration of the freezing increased, being 44 per 
cent for a duration of twenty-four days. 
Changes in the seeds produced by frost.—After the seeds had 
remained frozen for ten to twelve days a white, glutinous material 
oozed out at every slight break in the coat of the seed. A micro- 
scopic examination showed that the cell wall.and starchy protoplasm 
was almost entirely disorganized, but the starch granules themselves 
were entirely unaffected. Strange to say, the power of the seeds to 
germinate was not destroyed by this. (Agr. Sci., Vol. IV, p. 337.) 
Protection from frosts—The formation of artificial clouds of 
smoke for the protection of plants from frost is generally successful, 
and should be resorted to in critical cases; thus, in a vineyard at 
Pagny about 3 a. m. of May 13, 1887, when the temperature was 3° F. 
below freezing, hquid tar was ignited, which had been poured into 
tin boxes, as also pieces of solid tar. Large clouds of smoke quickly 
enveloped the vineyard; the fires lasted for about two hours, but the 
smoke lasted considerably longer. All injury to the plants by frost 
was entirely prevented. (Agr. Sci., Vol. I, p. 172.) 
INJURIES AND BENEFITS DUE TO WIND-BREAKS. 
Protection against the injurious effects of wind may be obtained 
by the use of wind-breaks, which are usually made by planting a 
couple of rows of trees on the windward side of the field, or by so 
arranging the plantation that the hardiest and most vigorous decidu- 
ous trees are on the windward side. According to Bulletin No. IX 
issued by the Cornell University Agricultural Experiment Station, 
the benefits derived from wind-breaks are the following: Protection 
from cold, diminution of evaporation from soil and plants, diminu- 
tion of the number of windfalls, diminution of lability to mechanical 
injury to trees, retention of snow and leaves, facilitation of outdoor 
labor, protection of blossoms from severe winds, protection of trees 
from deformity of shape, diminution of evaporation and drying up 
of small fruits, diminution of the encroachment of sand or the loss 
of dry soil or the scattering of rubbish, increased rapidity of matur- 
ity of fruits, and encouragement of birds that are beneficial to 
agriculture. 
Among the organisms arrested by wind-breaks and usually reckoned 
as an injurious climatic influence are the fungi or the spores of fungi. 
