A snow globe is a delicate glass or plastic spherical ornament filled with glitter or "snow" particles, some type of scene or decoration and a clear liquid. This liquid is usually water, glycerin or a combination of the two. When shaken, the glitter or faux snow distributes through the liquid and simulates snowfall as it settles back onto the floor of the ornament. Over time, the liquid inside a snow globe may leak or slowly evaporate. It is often possible to add water to a snow globe in order to restore it back to its original beauty.
Remove any musical components from the underside of the base first. These are usually attached to a cardboard or thin wooden panel, which is then screwed into the base. You will likely find the plug to the snow globe hidden beneath this panel. Using a small Phillips head screw driver or appropriately sized tool, unscrew and remove the musical paneling, ensuring you do not damage the wind-up mechanism in the process. Set the musical components aside in a dry, safe area.
Check the underside of the snow globe's base for a bladder plug. This is a small silicone or plastic plug that keeps the water inside the globe. If your globe has this plug, hold the snow globe firmly between your knees and pry out the plug with a utility knife. Fill a plastic syringe with water and carefully add water to the globe through the hole until it is completely full. Press the plug back into place, tapping it gently with a small craft hammer. If the globe previously leaked, seal the plug into the globe with a ring of clear epoxy. Let it dry upside down for several days.
Unscrew the globe from its base if the plug is not visible from the underside of the base. This is usually only possible with plastic globes. Turn the globe upside down and find the small plugged hole on the underside, usually below the figurines or scene in the globe. Unplug the hole and slowly add water with the plastic syringe until there is no air left, to minimize the chances of an air bubble in the globe. Replace the plug, sealing it with a thin layer of clear silicone or epoxy. Let it dry for at least 24 hours, then screw it back into its base.
If you want your snow to fall slower, add a combination of water and clear glycerin to the globe instead. The glycerin is more viscous than water and slows down the snowfall.
Do not attempt to refill a sealed glass snow globe. Even expert restorers sometimes accidentally shatter the glass. Drilling holes into glass requires special expertise, safety equipment and highly specialized tools. Take your globe to an expert restorer for refilling if yours is of the sealed, glass variety.