22 



THE AMERICA:^ MONTHLY 



[February, 



the necessary experimental rigor, M. 

 Freire has accomplished the attenua- 

 tion of the virus of the fever in a cul- 

 ture liquor, and the transformation of 

 it into a mild or vaccinal virus. In 

 the month of last November the Em- 

 peror of Brazil, that illustrious Magce- 

 nas of science, assisted by the ministry 

 of the Empire and the principal 

 members of the medical faculty, 

 wished to perpetuate the work of M. 

 Freire, and authority was given to 

 begin the vaccination of human be- 

 ings. The facts given by us have 

 not been tardy in producing results, 

 and in four months the number vacci- 

 nated exceeded four hundred. 



The phenomena observed to follow 

 vaccination are only those which are 

 noticed in a very mild yellow fever : 

 intra-orbital and supra-orbicular 

 pains ; very intense cephalalgia ; loss 

 of appetite ; elevation of tempera- 

 tui'e ; lassitude in the limbs. But all 

 these symptoms cease at the end of 

 two or three days at the most, and 

 the subject returns to health. If the 

 blood of a vaccinated case is exam- 

 ined some hours after inoculation, the 

 micrococcus of yellow fever is found 

 in the blood, but its enveloping coat 

 is no longer transformed into pto- 

 maine; it is consequently no longer 

 a poison, and is absorbed little by lit- 

 tle and finally disappears. 



The experimenattion has not yet 

 been able to demonstrate for how 

 long a time the immunity conferred 

 by this preventive inoculation will 

 continue ; but this immunity at the 

 outset is absolutely certain, and ex- 

 amples the most striking have demon- 

 strated it to us. Amidst us large 

 numbers of those inoculated have 

 been able to live in localities posi- 

 tively contaminated, seeing every day 

 around them the yellow fever thin- 

 ning out the ranks without experienc- 

 ing the slightest attackof the malady. 

 We have seen likewise in the course 

 of our experiments at that time, under 

 the influence of the high temperatures 

 of these regions, the laboratories to 

 become literally invaded by the mi- 



crobe, animals recently purchased as 

 subjects of experiment to die of yel- 

 low fever spontaneously and in a few 

 hours, while certain others inoculated 

 for prevention have perfectly resisted, 

 giving all the signs of perfect health. 

 I close by claiming to establish for 

 M. Freire the question of priority, 

 and in promising to give very soon 

 new details, supported always by ex- 

 periment. 



o 



The Study of Yegetable Fibres. 



In the National Museum there is a 

 large and valuable collection of tex- 

 tile fibres, which shows that the 

 world is by no means dependent 

 upon the best known fibre-yielding 

 plants, cotton, hemp, flax, and jiite, 

 for its textile fabrics. Cotton and 

 linen cloths are so common and so 

 cheap among us that we scarceh' 

 think of the possibility of any substi.- 

 tutes for them. Yet in other lands 

 the conditions may be very different ; 

 and it is interesting to look back 

 among the early inhabitants of the 

 world, and trace the progress of the 

 textile industry through its various 

 staeres. We see how each nation has 

 learned to utilize the materials nature 

 has pi-ovided ; where cotton w^as 

 abundant it was woven into cloth, 

 where the flax and hemp flourished 

 their valuable fibres were extracted ; 

 fine linen is a ver}- ancient fabric. 

 This part of the subject, however 

 interesting, cannot be dwelt upon 

 here, nor can we refer to the circum- 

 stances which have led many persons 

 to spend much time and money in 

 the cultivation of other fibrous plants, 

 and inventing machinery to extract 

 the fibres from them. It would seem 

 that nothing could supersede cotton 

 for spinning and weaving such fab- 

 rics as are most constantly in demand. 

 Yet it may be that the time is not far 

 distant when it can no longer be said 

 that 'cotton is king.' Even now it 

 has a rival in the ramie, the Chinese 

 nettle, Bcehmeria nivea^ in the fine- 

 ness to which it can be spun, for the 

 pure white, silken fibres of the ramie, 



