valuable for habitation or culture, the danger rather lies 
in the other extreme, that the country will become so de- 
nuded of forests as to render the climate too dry for 
the profitable pursuit of agriculture. This has, in fact, 
_ mand the most serious attention. In many parts of the 
- continent of Europe great efforts are now being made to 
restore a portion of the forests which have been ruthlessly 
destroyed. At one Government establishment in Dal- 
 matia five million young trees are now in cultivation for 
this purpose. In our Indian possessions the evil result- 
_ ing from the destruction of the forests reached some years 
_ ago so gigantic a dimension as to demand the instant in- 
_ terference of the Government. The Indian forests are in 
themselves a source of great revenue, producing the most 
_ valuable teak, and multitudes of the more ornamental 
woods used in cabinet-work. But, independently of this, 
_ the most injurious consequences had resulted to the climate 
‘from their wanton destruction; the droughts, becom- 
‘ing constantly more frequent and of longer duration, 
brought terrible famine in their rear; and the swollen 
‘water-courses, when the rain did come, caused fearful 
devastations. The Government at length took the subject 
up, and in all our Indian Provinces the Conservancy of 
Forests is now an important branch of the Administration, 
though much yet remains to be done in consolidating and 
‘perfecting the system. In Mauritius similar results 
have followed similar causes. The fertility of the island 
has been diminished by the destruction of the forests ; 
and the fever which a few years since decimated Port 
_ Louis is attributed to the malaria occasioned by the floods 
bi ought down by the torrents swollen far beyond their 
ordinary dimensions. 
_ The literature of Forest Conservancy is, in fact, now 
enormous. Thestandard work on the subject, as far as 
India is concerned, is by Dr. Cleghorn,* the Conservator 
for the Madras Presidency, which gives a history of what 
our Government has been doing there. We are constantly 
eceiving, however, from others of our colonial depend- 
encies, official reports of the efforts being made in them 
for the preservation of the native forests ; and it is im- 
possible in this connection to avoid mentioning the name 
he Botanic Gardens at Melbourne, whose exertions in 
the introduction and acclimatisation of Australian forest 
es in other climes have been unwearied and of inestim- 
able value. : : 
In Algeria the same tale is told as in India. Up to 
out the year 1865 the wanton destruction of the forests 
the Arabs by fire and other means, was enormous ; un- 
at length the French Government took up the subject, 
vbly aided by one or two English and French owners of 
landin the Colony. The tree found there most efficacious 
in repairing the waste, is not a native, but one of the 
ily known in Australia as “ gum-trees,” the Eucalyptus 
buldus of Tasmania. The great advantage of the planting 
of this tree is, not only the value of its timber, but its prodi- 
ously rapid growth, said to be fully twenty times greater 
thanthat of the oak, It has been introduced also with 
_ ~_ ***The Forests and Gardens of South India.” By Hugh Cleghorn, M.D. 
F.L.S, (London; W. H. Allen and Co., 186r.) 
country. The foliage is said to secrete a gum-resin, which 
acts as a most valuable antidote to malaria fever. 
In the French department of the Hautes Alpes, an in- 
teresting experiment has been tried of a somewhat differ- 
ent character. The same results had there ensued from 
the same causes. Year by year the mountain villages had 
been abandoned, and in twenty years a diminution of 
population to the extent of 11,000 had taken place. An 
attempt to replace the forests met with the most violent 
opposition from the peasantry, and they were al- 
lowed to substitute “ gazonnement” for “ reboisement ;” 
that is, the people were compelled to returf the barren 
and neglected districts. The effect is said to have been 
most beneficial. The fresh covering of the naked soil 
has prevented evaporation, and has allowed the rain to 
sink in instead of running off in destructive torrents ; 
and districts which a few years ago were abandoned to 
desolation are now gradually acquiring a luxuriant vege- 
tation, and giving food and shelter to the flocks and herds 
which had long been strangers to them ; the streams are 
becoming clearer and less violent, and the bridges are no 
longer periodically carried away. 
There is probably no department of Science to which 
human energy and ingenuity could be more profitably 
turned than the reclaiming of the waste places of the 
earth. 
DANA ON CORALS 
Corals and Coral Islands. By James D. Dana, LL.D. 
&c. (Sampson Low and Co., 1872.) 
HE distinguished naturalist, geologist, and minera- 
logist, who is the author of this semi-scientific work, 
is probably, next to Charles Darwin, the man from whom 
an expansive book on coral formations would be expected. 
He has had immense opportunities for the careful investi- 
gation of all the phenomena of coral reefs, and his peculiar 
mental constitution has assisted him in all his endeavours 
to teach and to arrange. No geologist has equalled Dana 
in the arrangement of his work ; and his celebrated book 
on that science is eagerly studied by teachers of all degrees. 
As a student of details, he may point to his Mineralogy 
with great pride ; yet, with these powers and gifts ready 
at hand, Dana produces, late in life, this disappointing 
beok. It is full of precious stones in ugly settings, and 
the gems are intermixed with much that is worthless. To 
the general public it will be almost a closed book for years 
and it is hardly worthy of a place in a purely scientific 
library. A great portion of the book is taken up by de- 
scriptions and remarks upon animals which are not corals, 
and which in no way affect or produce coral reefs or islands, 
and the old errors respecting coral productions are per- 
versely introduced. All the notices and descriptions of the 
Actiniz and Hydroidea might have been omitted, as 
they only confuse the subject, and surely such statements 
as refer coral making to (1) Polyps, (2) Hydroids, (3) 
Bryozoa, (4) Algee, might have been left buried in the 
memories of those who have been teaching that the third 
and fourth named organisms have nothing to do with 
coral any more than oysters and sunflowers. 
Writing about Actiniz, Dana gives the following without 
reference :—“ As to senses, Actinize, or the best of them, 
| are not so low as was once supposed ; for, besides the 
