Mystery Solved: How the Hippodrome Mermaids Survived Under Water

Almost immediately after the show's debut, the New York Times observed, "No spectacular invention or innovation of recent years has aroused such popular curiosity as the mermaid scene in Neptune's Daughter at the Hippodrome.  The mermaids, who are only mortal actresses and by no means amphibious, first rise to view in the very midst of the tank, which is supposed to represent the briny deep."

Mystery and curiosity, the producers believed, would draw crowds:

The rehearsals, when there was any danger that the scheme might be revealed, were conducted with the utmost secrecy.  Every attache of the Hippodrome who had an opportunity to discover the truth was solemnly pledged to tell nothing.  The mermaids 'hoped they might die' if they told, and knew they would lose their positions in case they had the hardihood to break faith with the management.  The projectors of the enterprise believed that the greatest advertisement that they could have would be the greatest mystery they could muster.  For business purposes, they protected themselves with patents.  For box office purposes, they determined to mystify the City of New York.

Where there is a mystery to solve, someone will solve it.  Where there is a story to leak, someone will leak it.  

How the mermaids in the Hippodrome production of Neptune's Daughter enter and go out apparently through the bottom of the tank, how they contrive to go under water at will and stay down until it is time for them to come to the surface again, has been discovered.  It is not really so wonderful.  In fact, this apparent marvel of modern science is merely an adaptation of the diving bell principle, which was worked out a great many years ago.

The ordinary diving bell is a hollow, air-tight cylinder, open below and furnished with a contrivance for supplying it with air, so that in it persons may work in deep water.  The only essential difference in the diving bell apparatus used for Neptune's Daughter is that the air chamber is square rather than round, and it is supported on iron rods from the bottom of the tank instead of being lowered from above. 

Each mermaid is provided with a separate diving 'chamber,' or whatever word may be coined to meet the exigency  The closed top is perhaps a couple of feet below the surface.  This chamber is open at the bottom, but, like the diving bell, it does not fill with water because of the air within.  A practical illustration of the principle may be given by pushing a common tumbler, bottom down, into a pail of water  It will be observed that the glass fills only in part.

The air pressure inside the mermaids' chambers is not oppressive because these are so slight a distance below the surface. 

At the beginning of the act, each mermaid is already established in her submarine compartment.  Bubbles of air may be observed on the surface of the water.  Sirene, the Queen mermaid, first rises to the surface.  All she has to do is to drop through the open base of the chamber, rise to the top of the water, swim a couple of stokes, and place herself on top of her hidden shelter. Around the roof, so to speak, there is a little railing that she may run no risk of making a sudden misstep and tumbling back unceremoniously into the deeps of the Hippodrome tank.

The other mermaids rise similarly from their chambers, which are placed in a semi-circle around the front of the tank. The wonderful dog that Marceline [the Hippodrome clown] pulls to the surface manages to live underwater in the same manner.

Getting back into the chamber is more difficult. There is nothing "faked" about the diving.  Each girl must dive down below her compartment and then rise into it through the bottom.  But in each chamber a man is posted to catch the girl and pull her in, so that there may be no chance of her missing her objective and possibly rising to the surface when she shouldn't be there.  Once out of sight, she has merely to take her place in her submarine shelter until the end of the act.

The chambers are not as uncomfortable as might be imagined, small though the quarters necessarily must be.  The mermaid can sit down and while away her time as suits her fancy.  A supply of fresh air is constantly  being forced in through pipes from above.  The little room is lighted by electricity  There is even telephone connection with the outside world behind the scenes. If she feels so inclined, the girl can even use her submarine powder-puff.

The most complicated matter in the carrying out of the illusion is arranging for the entrance of Neptune, who rises to the surface in his barge, accompanied by mermaids.  Yesterday afternoon the barge stuck half-way up, as it appeared between the back edge of the tank and the nearest concealed chamber, and had to be pushed off before it could rise fully to  view.  Someday the  barge may rise without Neptune and his mermaids if they happen to miss the signal and don't leave their chamber to get aboard at exactly the right moment.  When the barge with the heroine on deck, sinks again beneath the waves, every one must take a long breath, for the descent is far less rapid than a dive. 

When the sailor hero plunges into the tank, he knows precisely where to plunge to find the chamber that is waiting for him.  The clown and the others who make futile attempts to follow the mermaids to the bottom are merely not fortunate enough to have been provided with apartments. 

Though this may all seem mechanical in the narration, it is only just to the managers to add that the illusion is perfect. The visual mystery is absolute--so absolute that most people have jumped to the conclusion that the water was a mirage and the whole thing contrived with mirrors.  The mermaids are protected from the cold by rubber undergarments.  Their costumes are of a sort not to be affected by wet, their grease paint is not removable with water, and their wigs are curled on wire.  Such are the joys of being a 'tank actress'!
                                                                                                 --New York Times, Dec. 1, 1906