"The above account renders it unnecessary for me to dilate 

 further on the importance of similar results. I shall be satisfied 

 if I succeed in inducing either private individuals or the 

 Government to make use of this process of sanitary improvement." 



It is to be observed that M. Gimbert attributes the sanitary 

 effect of the Blue Gum to two causes : (i) the effective drainage 

 of marshy soil resulting from the rapid growth of the trees and 

 the constant transpiration from the leaves of the water taken up 

 by the roots ; the influence of their " antiseptic emanations " on 

 the " organic miasma " to which at that time malaria was attri- 



As to the first, the facts were undoubted. As to the second, the 

 statements were purely hypothetical, and Kew preserved an atti- 

 tude of discreet scepticism. Notwithstanding a " boom " for 

 planting Blue Gum and other species of Eucalyptus spread over 

 the world. An attempt was made at great expense to correct the 

 unhealthiness of the Messaria Plain in Cyprus by planting young 

 Eucalyptus trees, to be promptly killed by the first frost. 



Doubt, in fact, was from time to time thrown on many of 

 M. Gimbert's facts, and the value of planting Blue Gum in com- 

 bating malaria became more than doubtful. 



In a letter to the British Medical Journal (Sept. 27, 1884), Dr. L. 

 Aitken, of Rome, denied the correctness of the statement that had 

 been repeated over and over again, that the sanitary state of the 

 neighbourhood of that city had been improved by the plantmg of 

 Eucalyptus trees. Except at Tre Fontane, he says, where the 

 unpaid labour of monks and convicts keeps the trees alive the 

 experiment of planting the Campagna has proved a costly failure, 

 only three or four per cent, of the trees planted under the con- 

 ditions attending the plantation of other young forest trees having 

 survived. Even at Tre Fontane the Government has found it 

 necessary to restrict the amount of convict labour which it at first 

 placed at the disposal of the Trappist monks for plantmg opera- 

 tions, in consequence of the sickness among the warders and 

 convicts. The monks themselves, too, are known still to succumb 

 to malaria, though Dr. Aitken more than hints that the whole 

 truth is not made public, lest it should affect the sale of the 

 Eucalyptus elixir which is prepared at the monastery and adds 

 materially to its revenue. Dr. Aitken does not deny that the 

 deaths from severe malarial fevers have decreased during the last 

 year or two, but apart from the fact that this ^fy be due to 

 fluctuations in the intensity of the malarial poison, he iB inciinea 

 to attribute any slight improvement which may be claimed quite 

 as much to the necessary subsoil draining and preparation ot tne 

 ground as to any influence of the young gum trees. 



M. Charles Riviere, Director of the Jardin d'Essai »] Algi«™' 

 wrote as follows in 1885 {Bull, de la Soc. Nat. d'acchm. de France, 

 Jan., pp. 17-18) :— ^^ . 



« I think I ought to call the attention of the Minister of Ma^ne 

 to some exaggerations with which public opinion has been p eased 

 to invest the qualities of this Australian tree, especially wom a 

 hygienic point of view. Many of the legends P^^lished about 

 this arborescent Myrtacea do not at present rest on any scientinc 



