They are call "Pince-nez".
The name comes from Frenchpincer, "to pinch", and nez, "nose".
They reached their peak popularity around 1880 to 1900.
A pair of spectacles is a pair of lenses set in a frame worn on the nose and ears in order to correct deficiencies in eyesight.
The middle part of a pair of spectacles is called a bridge or a nose bridge. This is the part of the spectacle frame that forms a bridge from one side of your nose to the other.
The 'bridge' of the nose - is the part right at the top where it joins the skull. The bit where you rest your spectacles.
That style of spectacles is called pince-nez, which means "pinch nose" in French. They have a nose bridge that pinches onto the nose to stay in place without the need for ear pieces.
Pince-nez spectacles are worn by placing them on the bridge of one's nose and pinching the frame to the nose. They do not have earpieces and simply rest on the nose. They were worn as early as the 15th century, however, became more popular starting in the 1840's.
Glasses/ spectacles. They sit on the bridge of your nose and you can see through them.
Spectacles were first invented in Italy in the late 13th century. They were initially made with glass lenses set in frames that could be balanced on the nose.
Franklin Delano Roosevelt, 32nd President of the United States.
Franklin Delano Roosevelt, the 32nd President of the United States.
Spring first into the engine.
The same person as if they were not wearing spectacles. Spectacles are worn to correct vision disorders.
There is no specific collective noun for 'spectacles' (or 'eyeglasses), most likely because spectacles aren't normally found in groups. However, if there is a group of spectacles, any noun suitable for the situation can function as a collective noun; for example a box of spectacles, a pile of spectacles, a row of spectacles, etc.