This paper is only available as a PDF. To read, Please Download here.
To read this article in full you will need to make a payment
Purchase one-time access:Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
One-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:Subscribe to Respiratory Medicine
Already a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
1We are indebted to the Editor of the Lancet for the provision of the blocks from which the accompanying illustrations have been prepared.—Ed. B.J.T.
© 1934 Published by Elsevier Inc.