The purpose of this section is to provide a few more details about the dome, particularly the Lanphier shutter.

The two photos below show the exterior of the dome. The Lanphier shutter is shown on the left with its window near the bottom of the dome. Note the position of the main shutter above it, which extends over the top of the dome. When the shutters are moved upward, the Lanphier window is at the top and the main shutter has rolled completely over the top and down to the other side. The box along the skirt (bottom) of the dome (left photo) and below the window is where the wind screen is kept.

Left: Lanphier window at bottom                                            Right: Lanphier window at top
 

When the window is moved upward, the accordian like sheets of the wind screen are pulled out of the wind screen box. The main shutter resides above the window. The two shutters are hooked together but can be detached so that the main shutter can move up and down while the window remains below. What appears to be a handle above the window and on the main shutter is actually a stop limit device to prevent the shutter from going to far up or down. There are two such handles (stops) on the main shutter. Not easily visible in the tracks alongside both shutters is a large rubber seal extending along the entire length of the shutters, which prevents rain and air from entering the dome from above.

Left: Wind screen raised below the window                        Right: Main shutter above Lanphier window

To protect the glass window when the observatory is not in operation, a removable vinyl/metal cover is placed in the window. The window is hinged at the top and two latches on either side of the window allow it to be partially opened, so that the cover can be removed or replaced. The wind screen is attached to the window area from below and is drawn up and down when the shutters are moved. A wire on the right (barely visible) can be reached by the operator to disengage the Lanphier shutter from the main shutter. If the main shutter is brought down to the main shutter, they clamp together and act as one compete shutter. Two latches on either side of the window (barely visible in the photo on the right. One is just below the 'ee' in Screen.) allow the Lanphier window to be fastened in place or opened as in the photo on the left.
 

Left: Window cover partially inserted                                    Right: Cover in place, other window mechanisms

Metal flashing protects the roof from rain. It actually goes under the skirt of the dome about 8 inches. There is a slight incline to the flashing to allow water to roll off. The dome skirt is partially hidden in the photo on the left, but can be seen in the exterior photos of the dome above. Inside the dome, the photo on the right shows the basics of the shutter. There is a cogged track that runs down the middle of the main shutter assembly. A motor at the top, has teeth that fit into the track. There are two stops fastened on the shutter that engage a lever on the motor to stop the motor when the shutter reaches its up and down limits. They are adjustable, and look like refrigerator handles. One of the handles appears in a photo above.

Left: Flashing for the roof                                                        Right: Details of main shutter

The azimuth motor is clamped onto the azimuth track. The track contains holes for the cogs on the motor gear. Note the black rubber seal behind the motor and extending along the track. The seal helps prevent air from getting into the dome from outside.  The shutter motor is fastened to the dome wall near the top of the dome. A controller for each motor is provided but not shown.
 

Left: Azimuth motor                                                                    Right: Shutter motor hidden under metal box

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