Usage of "speak tube"

Encara no tenim significats per a "speak tube".

Ús de speak tube en anglès

The diaphragm and the speaking tube were the great sources of error. 
 Harvard Psychological Studies, Volume 1 / Containing Sixteen Exp... 

He barked a command down the speaking tube to the engine room. 
 Fevre Dream 

Inspired with an idea which promised hopefully, I raised the speaking tube. 
 The Return of Dr. Fu-Manchu 

Well..., Lady Maccon picked up the speaking tube and addressed her coachman. 
 Heartless 

He guesses the heft of them and shouts up the speaking tube. 
 The windup girl 

And there were dozens of roomers' cards over the dusty speaking tubes. 
 A Son of the City / A Story of Boy Life 

All parts of the vessel are in communication by means of speaking tubes. 
 Scientific American Supplement, No. 620,  November 19,1887 

At once Beverley took the speaking tube and ordered the chauffeur to stop. 
 The Lion's Mouse 

Mr. Parker lifted the speaking tube to his lips and gave an order. 
 An Amiable Charlatan 

Mr. Bixby said warningly through his speaking tube to the engineer- 
 Life on the Mississippi 

He pulled the plug from the speaking tube and barked into the brass. 
 Perdido Street Station 

Rue accompanied him to the navigation pit and picked up the speaking tube. 
 Imprudence 

Next she found the telephone wire cut and the speaking tube battered and inutile. 
 The Drums of Jeopardy 

Her lips were at the speaking tube in an instant. 
 Triple Spies 

She blew into the speaking tube and got a response. 
 Quest for the well of souls 

Numbers thirteen and six! she shouted into the speaking tube. 
 Library of Souls 

Significats de speak tube en anglès