January 13, 1888.] 



SCIENCE. 



17 



though every room in my cottage was thick with mosquitoes, ex- 

 cepting that of my daughter, there were only two of these insects 

 at any time observed in her room during the whole period of her 

 illness." 



W. W. Johnston, M.D., Washington, D.C., says, " In my own 

 family one case of scarlet-fever occurred : other children escaped. 

 In another family of eight children, isolation and disinfection pre- 

 vented the spread of the disease, but such instances are numerous.'' 



Charles W. Covernton, M.D., Toronto, Can., ex-president Pro- 

 vincial Board of Health, and Peter H. Bryce, M.D., Toronto, Can., 

 secretary of the Provincial Board of Health, relate an instance 

 where each succeeding member of the family took it at intervals 

 of three or four days. At the period when desquamation of 

 the first was beginning, a younger took a mild form of the dis- 

 ease. A few days afterwards conjunctivitis of both eyes appeared, 

 ending rapidly in the destruction of sight. The disease afterward 

 extended to the middle, with perforation, of tympanum, etc. There- 

 after the disease attacked the knee and elbow joints, with intense 

 suppuration and inflammation, ending in their destruction. The 

 child died on the twelfth day. There were some four or five chil- 

 dren in all. In the family of one of these physicians, a Cambridge 

 student had a book which he was studying at the time of the seiz- 

 ure with scarlatina. After his death, said book, with others that 

 had been open in the sick- chamber, were packed up and sent to 

 the latter's family in London, where they were placed in a garret. 

 Ten years after, a younger brother at Cambridge sent for these 

 works. Shortly after receiving them, he took scarlatina and died. 

 No other exposure to the disease was known. 



Dr. Bryce, in speaking of the methods to be adopted in prevent- 

 ing the spread of the fever, refers to an experience he had five years 

 ago, in the following language : " A child in a family in which there 

 were five children was taken with scarlet-fever. It and its mother 

 were put in an upper room, and the lobby cut off by a curtain an- 

 tisepticized with a solution of corrosive sublimate. The soiled 

 articles of clothing, etc., were placed in the same solution, and the 

 remnants of food were burned in the fireplace of the room. Seclu- 

 sion was perfect. At conclusion of desquamation every thing was 

 disinfected. No second case occurred in the family. Dr. Bryce 

 thinks the period of infection is not less than forty days. 



EXPLORATION AND TRAVEL. 



Transvaal. — The railroad from Delagoa Bay to Transvaal, 

 which was mentioned in Science, No. 245, has been opened from 

 Lorengo Marques to the boundary of the Portuguese Possessions. 

 It is somewhat difficult to form a correct idea of the state of affairs 

 in that region, as all news comes from English journals, and as the 

 English are in constant fear of an increase of Boer, German, or 

 Portuguese influence in South Africa. The Boers, of course, make 

 strenuous efforts to open a route to the sea independent of the 

 English, who threaten to swallow up the republics. This aim has 

 been achieved by the new railroad, the greater part of which runs 

 through Transvaal, and is in the hands of the Boers, while the part 

 now opened is in the hands of American capitalists. The opening 

 of this railroad, which was represented by English travellers as im- 

 probable, will result in a rapid development of the natural resources 

 of the Transvaal. Although a strong influx of Englishmen into 

 those countries may be expected, it is not probable that they will 

 swamp the Boer element, which has so long resisted the incessant 

 attacks of the English. 



Zanzibar. — The Sultan of Zanzibar, whose territories have 

 been reduced to a narrow strip of coast-line by recent treaties, has 

 leased his rights on the African coast between Wanga, at the 

 mouth of the Umba, and Vitu, to the British East African Associa- 

 tion. As he has made a similar contract with the German East 

 African Association, his rule is practically limited to the islands of 

 Zanzibar and Pemba and several parts of the coast that are of little 

 importance. The part of the coast leased to the British Associa- 

 tion includes the whole coast-line between the line of demarcation 

 between German and British influence and the German district of 

 Vitu. It is said that vigorous attempts will be made to open a 

 route from the coast to the Victoria Nyanza. 



Farini and Chavanne. — Dr. Hans Schinz, who made a long 



and interesting journey in South Africa, undertakes to expose 

 Farini, who claimed to have accomplished a long and hazardous 

 journey to Lake Ngami. He gives convincing proof that Farini, 

 who wrote a large volume on his adventures, never entered the 

 Kalahari, and never came into those remote regions in which he 

 claims to have made important explorations. Several passages in 

 his book had excited the suspicion of scientists ; and Schinz gives 

 now, in two letters to Petermann's Mitteihmge/i, conclusive proof 

 that his adventures and discoveries are one great fraud. The work 

 of another African traveller, J. Chavanne, has been justly and 

 severely criticised. Chavanne travelled for some time on the Kongo,, 

 and published the results of his observations in a magnificent vol- 

 ume, which is now shown to be largely an audacious plagiarism on 

 other publications on the Kongo, particularly Pechuel-Loesche's im- 

 portant work. Part of Chavanne's own observations are shown to- 

 be untrustworthy. Dr. von Danckelmann, who criticised Cha- 

 vanne, and Schinz, must be congratulated for their courage in expos- 

 ing these scientific impostors. Nothing should be more rigidly de- 

 manded from travellers than truth and a strict distinction between 

 their own observations and those of others. Those infringing these 

 rules cannot be too severely criticised. 



The Obangi. — Captain van Gele, who attempted to reach the 

 Welle from the falls of the Itimbiri last summer, but gave up his 

 plan on account of the difficulty of obtaining food at that point, left 

 Leopoldville on Oct. 2 on board the ' En Avant.' He proposed to 

 ■ascend the Obangi, and thus to ascertain its connection with the 

 Welle. It will be remembered that Grenfell succeeded in ascend- 

 ing the rapids of Zongo, which prevented Van Gele from exploring 

 the upper part of the river. After having passed these rapids. Van 

 Gele hopes to find navigable water and to reach the Welle. As it 

 is doubtful whether the Obangi receives a large tributary from the 

 east which may be identical with the Welle, he will carefully exam- 

 ine the left bank of the river, and explore important tributaries 

 which he may discover {Mouv.g^ogr.). 



MENTAL SCIENCE. 



Re-Action Time for Sensations of Temperature. 



In a recent number oiPfluger's Archiv of physiology, Vintschgau 

 and Steinach give a preliminary report of a series of experiments 

 upon the time necessary to perceive a sensation of heat, of cold, or 

 of contact with the skin in various parts of the body. The time 

 necessary for the mere feeling of contact on the middle of the fore- 

 head was for Vintschgau .119, and for Steinach .107, of a second. 

 The time of feeling a contact upon the right cheek was .119 and 

 .101 of a second respectively; and similar numbers for the volar 

 and dorsal surface of the left hand are .126, .128, and .133 and .lis 

 of a second. The results of their experiments upon the time it takes 

 to perceive a sensation of cold and of warmth are given in the table 

 below : — 



