This is a decorative Westmoreland Glass Dish manufactured between 1890 and 1930.
This glass dish comes in two piece: the lid of the dish is of a bird resting on the top of a nest made of foliage and twigs, and the bottom of the dish completes the nest and rests upon a stand of sturdier sticks and leaves. The entirety of the glass is colored light blue, and the company tag (albeit slightly scratched up) is seen on the bird's left wing. The tag should read "Westmoreland Glass - Hand Made".
The Westmoreland Glass Company was an offshoot of the Specialty Glass Company of East Liverpool, Ohio. Westmoreland would relocate to Grapeville, PA in 1889, in order to make use of the abundant natural gas in the area. One year later, production of a variety of glass products were overseen by George West as the president, and his brother Charles as vice president. After receiving the backing of one Ira Brainard of Pittsburgh, the brothers were able to buy out the Ohio Company and renamed it Westmoreland Specialty Company. 30 years of operation followed, with every conceivable type of glassware being manufactured by the company.
In 1921, George left the company to start one of his own, under the name George West and Sons. Charles would become president of Westmoreland while J.J. Brainard, son of Ira, became vice president. Using the designs that his brother George left behind, Charles would begin making high-quality hand-decorated glass from the 1920s through the '30s. Some of these pieces would find themselves in the Carnegie Museum in Pittsburgh. It is during this time when this particular dish would have been manufactured, as its form appears ideal for one of the many candy dishes that were being produced during the time.