"The Eucalyptus has been carried to other countries, and it seems to do well all over the world where the climate is not too cold for it. It grows rapidly, and is said to prevent malaria and fevers; we asked Doctor Bronson about the latter statement, and he said he was greatly inclined to believe it. The French introduced it into Algeria, and found that fevers diminished rapidly or disappeared altogether where it grew, and they are so thoroughly convinced of its utility that they have planted great numbers of Eucalypti. Mr. Bosisto, commissioner for Victoria at the colonial exhibition in London, 1886, discusses this subject thoroughly, and says that malarious diseases are not native to Australia, and imported fevers diminish in violence. He thinks this effect is caused by the Eucalyptus, which is evergreen and constantly exhausting humidity from the earth, and throwing off oil and acid from its leaf. A small quantity of Eucalyptus-oil sprinkled in a sick-room improves the air at once and renders breathing easier. Mr. Bosisto contends that the volatile oil thrown off by the leaf absorbs atmospheric oxygen and transforms it into ozone.
"The giant gums are sometimes called 'silver stems,' for the reason that after they have annually shed their bark—they shed their bark and not their leaves—the new skin is of the whiteness of silver. As the trunk is perfectly round, and the lowest limbs are often two hundred feet and more from the ground, the sight of a group of these enormous trees is a very fine one. The giant gums are more slender than the Big Trees of California; the former are the tallest in the world, but the latter have the greater diameter in proportion to their height.
"Next to the giant gum is the red gum, or Eucalyptus rostrata, and next to that is the blue gum, or Eucalyptus globus. The former is the finest timber-tree, while the latter is the most favored for its anti-fever qualities and is the tree most frequently carried to foreign lands. Don't expect me to go through the whole catalogue of Eucalypti, as there are fully two hundred of them, according to the botanists; the lowest and most wide-spread is the Eucalyptus dumosa, or mallee scrub, and you may judge of its extent when I tell you that a single tract of mallee scrub shared between South Australia and Victoria covers an area of nearly nine thousand square miles. 'And it isn't the largest area of scrub, either,' says an Australian at my elbow.
"Well, the mallee is a strange-looking plant, and I can compare it to nothing better than the frame of an umbrella turned bottom up and without any handle in the centre. It has a globular mass at its base, with a few horizontal roots, and then a long tap-root that goes down