During the gathering season it is astonishing how quickly these emptied cells will be refilled with honey, and not unfrequently the queen finds in some of these unoccupied receptacles timely provision for her otherwise contracted accommodation for depositing eggs; thus breeding goes forward at an astonishing rate. Much is written about the value of comb, and by this contrivance the labour of the bees in building it is saved. There is no doubt but that this instrument is of great service to the bee-keeper when judiciously applied,[23] and since the introduction of the movable combs it has formed an important adjunct thereto. For no invention has the apiarian cause to be more deeply indebted than for the "Mel Extractor" of Germany, improved upon as it has been both in America and in this country. Even if there were less sale for extracted honey, the extractor would be found at certain times of great value to every bee-keeper. In the award at the Philadelphia Exhibition, special notice of commendation is recorded of our honey-extractor. [Footnote 23: This, machine is not of much service for extracting honey from combs made in supers, the cells of which are mostly too soft to bear operating upon.] § XV. CHESHIRE'S NUCLEUS HIVE. The object of nucleus hives is explained below in the section on "Queen Rearing" (Chap. V. § vii.), and they render services in the process of artificial swarming, in maintaining a supply of young mothers, or in Italianising an apiary. Mr. Cheshire's contrivance is as follows; Certain frames in a regular hive are made to consist of two half-frames, each complete, but joined together in the top bar by a tongue in the one portion which fits firmly into an opening in the other, thus forming an ordinary frame except for the division down the middle. When a royal cell has been formed upon one of these compound frames, such frame is taken out of the hive, and the twin portions are then placed side by side in the nucleus, which measures only three and three-quarter inches wide inside, nine inches deep, and seven and a half from front to back. Its sides are constructed double in the same way as those of the Cheshire frame hive (page 145). In the nucleus hive it is necessary for the frames to be well covered up. Care must be taken that the queen was not upon either of the nucleus frames, but the other bees may be retained upon it. The older ones, however, will be sure to return to the stock hive, and their place must be supplied by shaking young ones off other frames on to a board in front of the nucleus.