217 
Sapindus Mukorossi Gsertn. (Sapindaceae). India and Japan. 
Schinus dependens Orteg. (Anacardiaceae). Bot. Mag. t. 7406. S. America. 
Tamarix gallica L. (Tamaricacese). Canaries, Trop. Africa. 
Thuja orientalis L. (Pinacese). " Arbor Vitse." China and Japan. 
Viburnum odoratissimum Ker. (Caprifoliacege). India, China, &c. 
Washingtonia filifera Wendl. (Palmse). California. 
Wigandia caracasana H.B.K. (Hydrophyllaceae). Bot. Mag. t. 4575. Venezuela. 
Zizyphus mucronatus Willd. (Rhamnaceae). Trop. and S. Africa. 
(/) Rain. Rain can destroy forests in two ways, by the formation of floods 
and torrents, which mechanically break down the forest and wash it away. This aspect 
of the subject is dealt with at some length under the title " Mitigation of floods by 
forestry operations." (See Part LVI, p. 130, of the present work. Also see " Forests 
considered in their relation to rainfall and the conservation of moisture," Part LV, 
p. 95.) 
The other aspect is the soil getting waterlogged, with little mechanical 
disturbance of the soil. The roots of the trees become drowned and the forest dies. 
Many trees, such as those known as " Flooded Gums " and " Swamp Gums," are 
accustomed to such conditions, as the result of a long environment, but in exceptional 
seasons there is some mortality from excess of rain. 
The effect of rain is always most serious when, the ground having got well sodden, 
violent gusts of wind ensue, and trees may be prostrated in great numbers. 
As to records of New South Wales floods, see Henniker Heaton.* 
H. Fires. 
t 
Here is another subject of practical importance to Australian forestry concerning 
which few data have been collected. We have had most devastating forest fires, yet, 
unless there be loss of life or of house property little notice is taken, for Australians view 
the destruction of virgin forest with a good deal of equanimity. As we have few working 
plans of our forests, and in many cases we do not know the various kinds of trees and 
their relative proportions in forest areas, we are unable to say, for example, what trees 
are the most inflammable. Mr. Rodney Cherry has madef some experiments in regard 
to the inflammability of certain timbers, and to some extent this would doubtless be 
a guide to the relative imflammability of the trees in a forest, but it must be borne in 
mind that the barks of certain trees are factors which must also be taken into account. 
A very superficial observation will show that barks are protective in a bush fire. 
For example, taking Eucalyptus, which forms the bulk of our forests, we have the 
succulent thick bark of certain Gums, the thick hard bark of the Ironbarks, and the 
* "Dictionary of Dates," p. 101. 
f " Comparative combustibility of timbers." " The Sydney Record " (Insurance Inatitute of N.S.W., Sept., 1903). 
