104 



NA TURE 



[May 30, 1907 



cells, that will support a man and an engine in a 

 moderate breeze. 



It will be interesting to watch the progress made 

 in the next two stages of Dr. Bell's programme, 

 which literally means the conversion of a kite into 

 a flying machine. These stages consist in mounting 

 his structure on a light catamaran form of boat and 

 propelling it on a water surface by means of aerial 

 propellers until it can be steered upwards into the 

 air. Whether this form of starting is as good or 

 as practical as running it on wheels remains to be 

 seen, but at any rate it seems the safest way to 

 commence with (Fig. 4). 



It may be mentioned in conclusion that not only 

 is this printed address accompanied by numerous 

 well-reproduced illustrations and a useful bibliography 

 relating to aerial locomotion, but all details concern- 

 ing one of the large winged-cell structures and the 

 interesting discussion which followed the reading of 

 the address are inserted. 



Among those who took a prominent part in this 

 discussion was Mr. Charles M. Manly, who, as he 



. 4. — A floating kite, adapted to be toW€d out of thi 



stated, " had the pleasure and the honour of being 

 associated for some seven years with the lamented 

 Secretary Langley as his assistant in direct charge 

 of the experiments which he conducted at the Smith- 

 sonian Institution." In his remarks it is good to 

 read that the work initiated by Langley is not aban- 

 doned, but merely temporarily suspended. In fact, 

 it seems quite probable that Langley's machine will 

 again be seen flying through the air, for Mr. Manly 

 proposes to re-equip and launch it again. To use his 

 own words : — 



" It is mv purpose at the earliest moment that I 

 ■can possibly spare the time for it, to re-equip the 

 aerodrome with proper supporting surfaces, and, 

 using the same launching apparatus, to give the 

 aerodrome a fair trial, this time over land instead 

 of over the water, when I feel very certain that it 

 will fully demonstrate the correctness of its design 

 and construction and crown Mr. Langley's researches 

 with the success which they so richly deserve, and 

 I trust that the day that this will be achieved is 

 very near at hand. It was tl^e launchin.'j .noparatus, 

 all will remember, which in both of the experiments 



NO. 1961, VOL. 76] 



caused the accidents that prevented any test of the 

 aerodrome itself. These accidents were not due to 

 defects in the design or fundamental construction of 

 the launching apparatus, for the smaller apparatus 

 of exactly the same design had been used more than 

 thirty times for launching the smaller machines, and 

 without a single failure. Certain minute defects in 

 the releasing mechanism were the sole cause of the 

 trouble." 



MALTA FEVER. 

 A Lesson in Preventive Medicine. 

 CITUATED in the midst of the Mediterranean, 

 *--' swept by all the winds of heaven, and enjoying 

 brilliant sunshine for several months in the year, the 

 island of Malta should be one of the healthiest of 

 places. Its freedom from swamps or standing water 

 of any kind protects the island from that scourge of 

 warm climates — malaria. For many years past, how- 

 ever, Malta has suffered from the prevalence of a 

 serious local fever, of a most per- 

 sistent character, which has been 

 the bane of the island, and par- 

 ticularly of the garrison ; for a 

 large fraction of the naval and 

 military forces has been con- 

 stantly incapacitated by this 

 disease. Every year some 650 

 sailors and soldiers have fallen 

 victims to it, and, as each patient 

 stays on an average 120 days in 

 hospital, this gives a total of 

 about 80,000 days of illness per 

 annum. Moreover, most of these 

 men have to be sent to England 

 to recover their health, and the 

 consequent expense has involved 

 a very considerable loss in money 

 to the Government. 



This fever appears to be widely 

 distributed in the world, but is 

 most familiar to us in its inci- 

 dence around the coasts of the 

 Mediterranean. On the island of 

 Malta it has worked its worst 

 ravages, and hence the name of 

 Malta fever, by which it is best 

 known. 



Now, however, all this has been 

 changed by a simple application 

 of the discoveries of science, and widespread gratifi- 

 cation will be given by the intelligence, fur- 

 nished in recently published reports, that since 

 June, 1906, when the new preventive measures 

 were put into practice, Malta fever may be said to 

 have practically disappeared from the garrison of the 

 Island Fortress. 



What are these preventive measures, and how has 

 this result been achieved? 



The serious ravages of Malta fever made it desir- 

 able that a searching investigation should be taken 

 in hand. In 1904 the Royal Society, at the request 

 of the Admiralty, the War Office, and the Colonial 

 Office, undertook to investigate the causes of this 

 fever, and sent out a small commission to Malta for 

 that purpose. This commission, which consisted 

 chiefly of Army and naval medical officers, has been 

 at work for three years, under the supervision of a 

 committee of the Royal Society, and has only lately 

 completed its labours. It is unnecessary to describe 

 the details of the three years' work ; it is enough to 

 say that every likelv line of research was followed 

 in order to discover how man becomes infected by 



