Perhaps the greatest advantage the movable frame-hive possesses is, that a full knowledge can be attained of its exact state as regards the queen, the population, and the quantity of food in stock. During weather of a genial temperature, the combs may on any fine day be inspected, and thus, a knowledge being gained of the deficiency existing in a hive, the necessary means may be adopted for supplying the want. Sometimes such an examination will verify the fears of the bee-keeper, when, having observed that his bees have ceased to carry in pollen, he has thereby received warning that the queen has been lost at some juncture when no successor to the throne could be provided. Such a hive has entered on a downward course, and will dwindle away entirely, unless a queen should be given to it, or else some combs containing young brood not more than three days old. By the latter method, the bee-keeper will gain an opportunity of seeing the bees set about their wonderful process of raising a queen from the brood thus provided for them. When a bee-keeper has become skilful in his calling, he maybe desirous to encourage the breeding of queens, or rather of preventing their destruction. He will seek to use the propagating instincts of the worker-bees as a set-off against that innate hatred of rivalry which prompts the reigning queen to kill the tender royal brood. [Illustration] An ingenious little contrivance has been brought into use by continental bee-keepers, especially by Herr Kleine, a German pastor, to prevent the destruction alluded to. It consists of a small wire cage (in fact, a pipe cover), as represented in the above engraving, placed over a queen-cell to protect it from the mother-bee's animosity, and it also serves to prevent the young queen, when hatched, from escaping; for she will have the same jealous feeling toward her sister-princesses, should there be more in the hive. The bee-master may thus carefully remove and appropriate her. Particular attention will have to be exercised to affix the cage into the comb by pressure, as far as the middle wall, but at no point must it touch the royal cell itself. As the cage will probably project so as to touch the adjoining comb, a little incision and removal of a portion may be necessary, to allow space for it. It can, however, be squeezed into any shape to suit the position required. This covering need not be put over the cell until the egg is a little more than a week old. The animosity of the reigning queen does not generally manifest itself until the royal brood approaches maturity. It is said that these cells are unmolested on the tenth day, but that on the eleventh day they may be found tenantless. Notwithstanding the apiarian's care and skill, many disappointments are frequently experienced in endeavouring to establishing fertile young queens at the head of colonies.