820 EXPERIMENT STATION RECORD. 



Inoculation experiments were also carried out on various experimental animals. It 

 was found during these experiments that the organism was pathogenic for mice, 

 guinea pigs, rabhits, and dogs, and slightly so for fowls, horses, calves, and cats. 

 The morphology of this organism is descril)ed and notes are given on the pathology 

 of the affected ti.ssue. The organism, while referred to as a Streptothrix, is believed 

 to be more properly referred to the genus Actinomyces, and the author therefore 

 proposes the name A. hicolor. 



Roup, an experimental study, F. C. Harrison and H. Streit {Ontario Agr. CoL 

 and E.tjit. Farm Bui. 13^, pp. 4S,Ji(j!^. ;^5). — For many years this disease has appeared 

 in the poultry yards of the Ontario Agricultural College, usually during damp 

 autunm weather. It causes a direct loss of from 10 to 15 per cent of fowls and 

 attacks principally young l>irds. Detailed notes are given on the clinical symptoms 

 and 2>athological lesions of this disease in various parts and organs of the bodj\ In 

 pathological material obtained from diseased birds the authors demonstrated the 

 presence of Bacillus cacosmus, which is called the roup bacillus. Notes are given on 

 the behavior of this organism on various nutrient media. The virulence of the roup 

 bacillus, as first obtained was quite weak, but was increased by repeated passages 

 through pigeons. Numerous infection experiments by different methods were car- 

 ried out. It was found that in order to infect fowls experimentally it was necessary 

 to use roup bacilli from a culture which had been freshly isolated. Pigeons when 

 inoculated with a roup bacillus became infected and exhibited symptoms similar to 

 roup in fowls. Extensive necrosis of muscle tissue was produced by inoculation 

 with the roup bacillus. Feeding experiments with rouj) bacillus yielded negative 

 results. Several attempts were made to immunize fowls and rabbits, but without 

 any success. Inoculation experiments with Bacillus pyocyaneus showed that this 

 organism is capable of producing chicken diphtheria, but that its virulence is soon 

 lost by growing on ordinary culture media. 



Treatment of fowl cholera by Septicidin, Schmidt [Berlin. Tierdrztl. Wchnschr., 

 1903, No. 37, pp. 421-423). — An outl^reak of this disease took place during the past 

 season in a village near Dresden and spread rapidly, showing a high virulence. The 

 author vaccinated 60 birds with Septicidin, including chickens and ducks. For 

 each bird 1 cc. of the serum was used. On another estate 36 chickens, turkeys, and 

 ducks were vaccinated with doses of 2 cc. of Septicidin. As a result of vaccination 

 of these fowls the rate of mortality from fowl cholera was reduced to 5 per cent, 

 while among birds which were not vaccinated the mortality was frequently 100 per 

 cent. According to the author's experience Septicidin may be used also in the 

 diagnosis of fowl cholera. 



AGRICULTTJRAL ENGINEERING. 



The testing- of road materials, L. W. Page and A. S. Cushman ( TJ. S. Dept. 



Agr., Bureau of Chemistry Bui. 79, pp. 77, pis. 6, figs. 10). — The main object of this 

 bulletin is to describe in some detail the methods and work of the road-material 

 laboratory of the Bureau of Chemistry of this Department established in December, 

 1900, and to give the results obtained up to the present time.. "Incidentally, the 

 physical, mechanical, and chemical agencies which act upon road materials are 

 discussed and a brief history of the testing of such materials is given." 



The principal activities of the laboratory are classified as follows: "(1) Tests for 

 determining the quality of materials to aid road builders in selecting those most 

 suitable for their work; (2) the investigation of various processes to develop simple, 

 appropriate, and reliable tests; (3) the collection of data for use in drawing up speci- 

 fications for standards of quality; (4) scientific research to develop new materials or 

 mixtures, and the study of problems which may arise in road building. 



"The most important work comes under the first head, for the main object of the 



