By means of differential centrifugation in the horizontal and angle centrifuges it is possible to obtain appreciable quantities of relatively pure elementary bodies of vaccinia. Such preparations of elementary bodies exhibit an extremely high titer of vaccine virus.

The elementary bodies are specifically agglutinated by serum from rabbits immunized by means of injections of bacteria-free vaccine virus.

Virus-free filtrates of dermal vaccine virus and of bacteria-free testicular vaccine virus contain a soluble substance or substances that is precipitated by antivaccinal sera.

This content is only available as a PDF.