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SCIENCE 



[N. S. Vol. XLI. No. 1052 



mosquitoes wafted! by winds are not obstructed 

 and are accumulated by foliage. Again, the 

 fact that malaria usually keeps near the sur- 

 face of the earth and is said to "hug the 

 ground " or " love the ground " corresponds 

 once more to the habits of mosquitoes. 



It will be unnecessary to take up any of the 

 further points, except to quote two significant 

 paragraphs as follows: 



In opposition to the mosquital origin of malar- 

 ial disease it is known that numerous mosquito 

 wounds may be inflicted without the occurrence of 

 malarial disease; but this is by no means incom- 

 patible with the theory. We do not yet know 

 whether the poison be mosquital saliva or 

 whether the fever-producing element be a bacillus 

 with which the puncturing proboscis of the in- 

 sect may be loaded at the time of inflicting its 

 wounds. The scratch of a lancet will not produce 

 vaccinia unless the instrument be charged with 

 vaccine matter; the puncture-needles of Pasteur 

 would be harmless and impotent, did he not load 

 them with infecting bacteria; so with dog-bites 

 and hydrophobia, etc. 



Again: 



Nay, it may even turn out that, under certain 

 circumstances, mosquito-bites shall even be pro- 

 tective against malarial disease, for as Pasteur 

 and others are able to produce, artifleially, "at- 

 tenuated culture-fluids, ' ' the inoculation of which, 

 while producing slight symptoms, protects from 

 more serious phases of disease, so may there exist 

 in nature naturally ' ' attenuated ' ' fever-poison 

 fluids, the inoculation of which, by mosquital 

 puncture, may produce trivial symptoms, and thus 

 protect from more decided attacks of veritable 

 fever. 



In the first of these paragraphs Dr. King 

 fully meets the objection which curiously 

 enough is raised to-day in the Bitter Root 

 Valley in Montana by the inhabitants who 

 claim to disbelieve the so-called theory of the 

 tick-transmission of the Rocky Mountain 

 spotted fever. " Why," they say, " We have 

 been bittenj by ticks many times and have 

 never had the fever." As King pointed out 

 iii these early days, they have not been bitten 

 by an infected tick. 



In the second paragraph he almost antici- 

 pates Koch's conclusions as to the immunity 



of native children in German East Africa, 

 even though he does not point out their 

 danger as reservoirs. 



It may be well to quote still another para- 

 graph which is of especial significance : 



In so far, therefore, as regards the geograph- 

 ical relation between mosquitoes and malarial dis- 

 ease, it may be said: (1) The two often coexist; 

 (2) there is no decided proof that localities al- 

 leged to be exempt from ague are also exempt 

 from mosquitoes; (3) there is no locality noted 

 for malarial disease -where mosquitoes do not 

 exist. 



Very naturally, in conclusion, the far- 

 sighted author mentions the question of pro- 

 phylaxis on the basis of his theory. He 

 points out protection to the individual during 

 the evening and night by gauze curtains, win- 

 dow-screens or clothing impenetrable to their 

 probosoes, or an anointment of the body with 

 some linimeiit; protection to the domicile by 

 screens or fences, or light traps, or the use of 

 smoke such as pyrethrum, or of a volatile oil ; 

 municipal protection by the destruction or 

 draining of swamps and pools, etc. 



It will thus be seen that malarial prophy- 

 laxis has made practically only one step since 

 the days of King, except in so far as meas- 

 ures are concerned which depend upon the now 

 knovra biological peculiarities of malarial spe- 

 cies. His system, included everything which 

 was done in Italy for many years after Ross's 

 discovery and which resulted in the lowering 

 of the percentage of malaria on the Roman 

 Campagna from 74 to 14, and his only omis- 

 sion from the present system is that of quin- 

 inization of the people at large as practised 

 by Koch in East Africa and by the late Dr. 

 Celli and his colleagues in Italy to-day. 



It is strange that so suggestive a paper as 

 this and, in fact, one so theoretically conclu- 

 sive, should have been received with so little 

 interest and have been so soon forgotten. 

 That Dr. King was a strong man is shown by 

 the fact that he was not in the least discour- 

 aged by his interview with so renowned an 

 entomologist as Riley, or by the lukewarm in- 

 terest with which his original paper was re- 

 ceived by the Philosophical Society of Wash- 



