Gas Mask Has Loud Speaker to Amplify Muffled Voice

Title (Dublin Core): Gas Mask Has Loud Speaker to Amplify Muffled Voice
Subject (Dublin Core): en Personal protection (chemical); en Communication; en Imagined technology & prototypes
Article Title and/or Image Caption (Dublin Core): Gas Mask Has Loud Speaker to Amplify Muffled Voice
Language (Dublin Core): eng
Temporal Coverage (Dublin Core): World War II
Date Issued (Dublin Core): 1940-02
Is Part Of (Dublin Core): Popular Mechanics, v. 73, n. 2, 1940
pages (Bibliographic Ontology): 191
Rights (Dublin Core): Public domain
Source (Dublin Core): Google books
Archived by (Dublin Core): Enrico Saonara