(1) There are two methods of examining industrial material for anthrax spores, viz. agar plate cultures and the inoculation of guinea-pigs.
(2) Though no worker has yet made a large series of examinations of equal portions of the same material by both methods simultaneously, yet the available evidence indicates that animal inoculation is superior, provided that guinea-pigs, not mice, are employed.
(3) It is better to inoculate two guinea-pigs than one, and to use the centrifuged deposit of the watery extract, though this practice may also increase the mortality from pathogenic anaerobes.
(4) The inoculation of guinea-pigs is more successful than plate cultures mainly on account of the larger quantity of watery extract usually tested, which more than counterbalances the disadvantage that some of the animals died from anaerobes before they develop anthrax.
(5) If plate cultures are employed it is essential to examine the superficial colonies after a short incubation, probably 12 to 16 hours is the most suitable.
(6) Anthrax spores have been demonstrated by the inoculation method in 21·3 % of 141 samples of industrial material, supposed to have produced anthrax in Liverpool amongst those who handled them. Of these samples 28·6 % were from hides, 22·2 % from wool, 20·6 % from hair and 7·1 % from bones. The largest proportion of infected samples came from Singapore.
(7) Anthrax spores have been demonstrated in one sample of hair “ disinfected ” with 5 % fluid of high coefficient at 100° C. and in two out of six samples of hair disinfected in Germany probably by steam at 105° C. It is practically impossible to completely sterilise certain industrial materials without seriously damaging them; yet partial disinfection should on no account be abandoned, because the perfect method has not yet been discovered.
(8) Anthrax appears to be steadily increasing among domestic animals, and consequently a larger number of agriculturalists are becoming infected. The reason for this dissemination amongst animals is still obscure.
(9) We have found B. anthracis in a sample of pea meal used for feeding cattle confined to a shippon, one of which died of anthrax. The meal was probably infected from the sack.
(10) Anthrax is preventible among men and domestic animals, and its ultimate suppression depends largely upon the certainty with which bacteriologists can demonstrate the presence or absence of bacilli in suspected industrial food, or other materials.