first (1879), together with Klebs, to discover the microbe of 

 malaria— the Bacillus malarice. In 1885 Crudeli published his 

 important and interesting work, ' The Climate of Rome.' It is 

 indispensable, he says, to form an exact idea of malaria and of the 

 conditions in which it is produced, to free the mind from the 

 prejudice that has taken possession of the medical fraternity, as 

 well as of the laity, that malaria can only be produced from 

 stagnant water, resulting from the putrefaction of dead vegetable 

 and animal organisms contained therein. It was thought that a 

 step forward had been made when the morbific ferment that 

 produces malarial infection was called paludine miasma ; but the 

 reverse was true. Italians use the word malaria to indicate the 

 specific agent of intermittent and pernicious fevers. Italy has 

 enjoyed the unenviable privilege of sending this word around 

 the world and causing it to be received into every language. It 

 has at least the advantage of not prejudicing any opinion with 

 regard to the nature and production of this specific agent. It only 

 specifies an established fact, namely, that this agent diffuses itself 

 in the atmosphere, making it capable of infecting human organisms 

 mto which it may have been introduced by respiration. 



"Malaria is produced in the soil and not in water. The sine 

 qua non of the production of malaria is the presence of malarial 

 ferment m the soil. Soils that do not contain this ferment may 

 possess every possible form of saturation by water, Avhich, in turn, 

 may contain all possible forms of putrefaction, but there will be 

 no production of malaria. Water is undoubtedly an indispensable 

 factor of this mischievous product, because if malarial soil is not 

 kept moist during warm weather, it is incapable of producing 

 malaria. Hence, all other conditions being equal, malarial soils 

 containing stagnant water are, by right, considered the most 

 dangerous, because in them is always found the humidity indis- ' 

 pensable to the hurtful product, even during the driest summers. 

 A }^ r^ ^? means necessary that the soil should be marshy in 

 order that malaria shall be produced. Were such the case, Italy 

 wouldbe a much more fortunate country than it is, because at 

 leasttwo4hirdsof Its malaria-producing soil would be perfectly 

 ^nM ^^; ^"f}'^^]^ li^miclity is required to awaken malaria in 

 so that contains Its germ, and we frequently meet with soil in 

 valleys, on hill-sides, and on mountains whose surface is arid 

 auring summer, but gives off malaria owing to the slight humidity 

 held in the subsoil. Nay, it can happen, Ld often does happen, 

 nrf ^'^f'JP^^l^t^^^! «f ^ater on the surface of a malarial soil 

 £!Zil J '^S''^'^ poisoning of the atmosphere. This always 

 happens when the water covers the infected soil uniformly. A 

 r]!?^o7J'f'*^''P'''®^ between the malarial-producing soil and 

 nrnf. f ?^P r ^^f ^*^' ^' ^^ ^^^^^^^^ to malarial germs and 

 protects the atmosphere of the locality from contamination. 



worsTf« /hL^^-?wf ^ '"^ ^ ^^^^*^^ «^ J^^ser deg'-ee- What is 

 rrth«f In k"^ *^^ exception of solid rock, we know of no 

 thl nL? ^^' «/^*«^^ declared to be incapable of generating 

 this infection of the atmosphere. Malaria is produced from soils 



