CHARLES OF THE WILD, by John and Ann Hassett, Houghton Mifflin Co., Boston, 32 pages, $5.95.

John and Ann Hassett, Waldoboro creators of the charming and clever “Cat Up a Tree,” have written another gem for young readers. “Charles of the Wild” should appeal to dog lovers, families who enjoy a good read aloud, and anyone young or old who has ever yearned for a bit more freedom.

Charles, a terrier, is the pampered and restless pet of a wealthy woman. He is never allowed outside unless he needs to be groomed or to acquire new clothes. And then he is carried. Heaven forbid he should catch a cold or get his paws dirty! His gourmet meals hold little appeal for him. And three times a day he is given nasty-tasting medicine. He does show his dissatisfaction by methodically chewing on his mistress’s shoes instead of his expensive toys.

Charles is only truly happy when he sleeps. He dreams of chasing rabbits, howling at the moon and running through forests. Then one day, he discovers an open window.

There are no foxes and wolves roaming the streets of Boston, but there are squirrels to chase. A homeless man shares a jelly doughnut with Charles. And he takes great delight in eating treats found in the dirt and drinking from puddles. In a delightful surprise ending, he is able to combine the best elements of his indoor and outdoor worlds to achieve a satisfyingly more liberated lifestyle.

The illustrations are rich and whimsical. When Charles is carried in his basket, there is a sharp contrast between the look of indignation on his little face and the dejected slump of his shoulders, and the purposeful stance and proud smile of his mistress. In a park scene, a woman tries in vain to feed a baby who is intent on removing her glasses, and a nattily dressed, book-reading man is assaulted by squirrels trying to steal his apple.

It’s not surprising that Charles is such a vivid and appealing creature. John wrote in a letter that he and Ann patterned the little fellow after a terrier they once owned.

“He was always running away. His name was Waldo, and he was a dog with wanderlust like Lewis and Clark and Columbus. We got phone calls at all hours of the day and night to come and collect him. He was a mischievous dog, with a talent for digging things up that are not to be dug up – like herb beds and Mrs. Gookin’s deceased canary. He could slip a leash faster than a jewel thief cracks a safe.”

As the Hassetts did in “Cat Up a Tree,” they have injected a lucid social commentary into a lively, fun adventure. “The setting for ‘Charles of the Wild’ is Boston’s Beacon Hill, a curious mingling place of the wealthy and the poor. Boston Common is a gathering spot for the city’s homeless. It was on a visit here that the story suddenly took shape in my head – a street person and a woman of wealth sharing the same dog.”

John really enjoyed creating “Charles of the Wild.” “I loved painting the bricks for some reason. My favorite picture is of Charles and the pigeons under the winged statue. It seemed funny to me to have the woman feeding pigeons beside the statue of the woman casting seed. I believe the statue is called The Ether Memorial and on it is inscribed, ‘Cast thy bread upon the waters, for though shall find it after many days.’ I think children enjoy finding adults in silly situations or behaving foolishly. I do.”