July 2, 1886.] 



SCIENCE. 



Vaughan, of the University of Michigan, has 

 recently investigated tlie poisoning of a number 

 of persons by ice-cream at Newton, Mich., and 

 is reported to have found tyrotoxicon present in 

 the ice-cream which produced the sickness. This 

 had been previously discovered by Professor 

 Vaughan in pieces of cheese which had caused 

 sickness, and which had been submitted to him 

 for examination. Whether this poison is due to a 

 germ, or to a chemical product, does not yet seem 

 established ; but it is but another proof of the pos- 

 sibilities of milk, either infected or decomposed, 

 acting as a factor in disease, and it is not im- 

 probable that diarrhoeal diseases so common 

 among the infantile population in the summer 

 months may be caused, or at least aggravated, by 

 milk which contains the tyrotoxicon. 



The bill authorizing the President to appoint 

 a commission to investigate yellow-fever and the 

 methods proposed for its prevention has passed 

 the senate, and, as there is now no opposition to 

 its passage in the house, there is every probability 

 of its becoming a law. In the mean while. Dr. 

 Preire, who claims to have discovered the microbe 

 of the disease and a method of inoculation to pre- 

 vent its ravages, is reported to have performed 

 the operation upon seven thousand persons living 

 in localities where yellow-fever is prevailing in a 

 most malignant form. Of this large number, but 

 •eight have died. During the same period, some 

 three thousand uninoculated persons have suc- 

 cumbed to the fever. Should the bill to which 

 reference has been made obtain a place in the 

 statutes, these claims of Freire will be subjected 

 to rigid investigation by the best American ex- 

 perts, and, if substantiated, will doubtless be the 

 means of introducing his system, or a modification 

 of it, into the United States, whenever yellow- 

 fever shall again appear in epidemic form. 



It has always been difficult to -understand 

 how the germ theory of disease could be true, and 

 yet the diseases which are due to germs could 

 vary so much in virulence ; at times being ex- 

 ceedingly mild, and again malignant in the high- 

 est degree. Dr. Sternberg, in a recent paper pub- 

 lished in the Medical news, makes this very clear, 

 thus removing what has to many seemed an in- 

 superable objection to the acceptance of the germ 

 theory. Germs which produce disease, that is, 

 pathogenic germs, are subject to great modifica- 



tion as regards this power. Germs which to all 

 appearances are the same, and which, so far as we 

 know, are in fact identical in most particulars, 

 may yet differ in their virulence ; being extremely 

 so under some circumstances, and but slightly so 

 under others. It is for this reason that virus may 

 be ' attenuated,' as it is termed. Thus the mi- 

 crobes which produce fowl-cholera in a fatal form 

 may, after two or three montlis, lose this viru- 

 lence, and still possess some pathogenic power. 

 It is this jprinciple of attenuation which enables 

 experimenters to inoculate animals with the same 

 microbe, but of gradually increasing virulence, 

 until perfect protection, even against the most 

 virulent form of the disease, is assured. A mild 

 attack of scarlet-fever is explained, therefore, not 

 on the ground that only a few microbes of the 

 disease exist in the body of the individual at- 

 tacked, for we know that this form of life multi- 

 plies with enormous rapidity, but by the probable 

 fact that the microbes in this individual case pos- 

 sess a mild degree of virulence. 



The further and deeper research is made into 

 tliis domain of bacterial life, the more apparent 

 does it become that disease-producing germs are 

 wide-spread and abundant ; and, if animals sus- 

 ceptible to any particular variety come in contact 

 with that variety, it is easy to understand how 

 disease may be contracted, even when no other 

 animal lias been brought in contact with them. 

 For instance : the bacillus which causes fowl- 

 cholera is found in various parts of the world in 

 putrid substances, and as a result epidemics of 

 fowl-cholera are most frequent among fowl that 

 are kept in unsanitary conditions. In the same 

 way typhoid-fever and cholera may develop irre- 

 spective of human intercourse or fomiies. Much 

 of this may seem trite, but the tendency of the 

 present day is to ignore filth as a factor in the pro- 

 duction of germ-diseases, and to limit their causa- 

 tion to the presence of other similarly affected 

 persons or animals, and to the articles which have 

 been in contact with them. In helping to clear 

 up the question. Dr. Sternberg has done good 

 service. 



THE ECONOMIC DISCUSSION IN SCIENCE. 



It is often doubted whether any good comes 

 of polemical discussion in a periodical ; and so 

 obvious are the disadvantages under which those 

 labor who would maintain a scientific position in 



