Can Saki's short story "The Lumber Room" be described as both humorous and serious? Justify your opinion.

Saki's story can indeed be considered both humorous and serious, for that is the nature of satire, and "The Lumber Room" is a satire of the upper crust of Edwardian England, the period before World War I.

Satire is a form of humor that ridicules social conventions, human faults and vices, people's stupidity, social abuses, political ideologies, etc. with the intent of both laughter and reformation of the flaws and shortcomings that it exposes. As a satire, Saki's story ridicules the stultifying lack of imagination within the rigid upper class system. For, in her adherence to the dictates of proper behavior, the aunt has lost any creativity which she might have possessed, and become narrow-minded in her treatment of the children and myopic in her judgments. Saki satirically observes,

She was a woman of few ideas, with immense powers of concentration. 

This self-appointed aunt decides things dogmatically without considering any variables; for instance, declaring that it will be "a glorious afternoon" for Nicholas' cousins to race on the sand, she sends these "good" children to the beach as a reward without considering the fact that the tide will be too far in for them to be on the beach, and without noticing the discomfort of Bobby, whose boots are too tight.

Because the miscreant Nicholas is imaginative, he outsmarts his aunt by making her believe that he wants to enter the forbidden gooseberry garden so that she will occupy herself in trying to catch him in disobedience. This trickery allows him to enter a forbidden lumber room, where many an artistic article sits gathering dust. In this room, then, Nicholas gives full rein to his imagination and has a delightful time looking at the creative teapot and the intriguing tapestry of a hunter who has impaled a stag with his arrow, accompanied by his two spotted dogs that are being watched by wolves. In the meantime, the aunt, who has diligently been watching the garden in order to catch Nicholas sneaking into it, falls into a rain trough. In her desperation, she must call Nicholas and bid him to enter the garden to save her. The clever and mischievous Nicholas refuses, however, asserting that his aunt has forbidden him, so the voice he hears must be the Evil One. Further, he "confirms" that she is not his aunt because he asks if there will be strawberry jam with tea and she says, "Certainly..."

"Now I know that you are the Evil One and not aunt," shouted Nicholas gleefully; "when we asked aunt for strawberry jam yesterday she said there wasn't any. I know there are four jars of it in the store cupboard, because I looked, and of course you know it's there, but she doesn't, because she said there wasn't any. Oh, Devil, you have sold yourself!"

Thus the aunt is defeated by her own narrow-mindedness and needlessly imperious behavior, presenting readers with a criticism of the autocratic and unimaginative natures of the Edwardians. At the same time, Saki delights his readers with the clever and imaginative character of Nicholas.