The "spreading chestnut tree is just a gray tombstone along the walk but modern Brattle Street retains much of the antique flavor that delighted Longfellow almost a century ago. All you have to do is look for it. Up past the bustle of the Post Office and retail shops stands the remains of Tory Row, a group of old houses which haven't changed much since they were confiscated by patriot fathers in the days of the Revolution. Several ageless landmarks lie between Story and Hilliard Streets. just a block from Brattle Square; and of these, Perhaps the most interesting is the building currently occupied by the Cock Horse Restaurant.

In this very house lived old Dexter Pratt, whose popular blacksmith shop had been built next door at the corner of Story Street. Walking daily between Craigie House and Harvard Hall, Professor Longfellow Habitually stopped to chat with the genial forget tender. A strong friendship developed between the two, climaxed in 1839 when the poet immortalized smithy in a work that has been chanted by American schoolboys ever since.

When Tyler A. Whit more bought the Pratt homestead in 1939, he faced a situation-not uncommon to historians-of several different families claiming direct descent from the original "Village Blacksmith." Most convincing of these were some people bearing the respected Boston name of Hancock. Interested in authenticating the legend once and for all, Whit more supervised a minute scouring of the Cambridge archives and concluded that Dexter Pratt was the most logical hero of Longfellow's poem. One Torrey Hancock, whit more found, did build the house and operate the smithy; but he sold out to Pratt in 1823, twelve years before Longfellow was appointed to Harvard.

The old Pratt place became a restaurant in 1913 when it was purchased and restored by Miss. Frances D. Gage, and open days the Cock Horse Inn. But that time Cambridge had long since parted with her cherished "chestnut three", in favoring of widening Brattle Street. But what the Cock House lacked in hallowed foliage, it made up in wholesome tasty food. Before long its fame as am eating place had spread throughout New England. This to the extent that a rhapsodic passage on "crab meat souffle" a la Cock Horse may still be read in Donald Heinz's "Adventures in Eating."

Whitmore, who assumed active management of the restaurant this year, is working in conjunction with Wentworth L. Hayes, better known to local gourmets as the steward of the Adams House kitchen. Although a Swedish woman has been in charge of the cooking for some sixteen years now, all food is prepared in the strictest New England tradition.

Both the name, Cock House, and the three-foot wooden animal that hangs over the door to the house are curious mysteries to the present owner. Nobody seems to know how either of them originated.

Besides food and tradition, the present restaurant specializes in what Hayes likes to call "something a little different." You enter the shuttered brown-wood building from a stone garden-path leading to the side door. Once inside, you are ushered into a waiting-room, with prints on the walls and the latest magazines on the tables.

From this point, the responsibility is yours. The ultra-venerable of Tory Row dowagers, who congregate regularly at the Cock Horse, generally choose one of the downstairs rooms where the rule is dignity, restraint and no smoking. Above, there are six semiprivate rooms where graduate students and professors are wont to soft-talk over their coffee. No liquor is sever in any of the various chambers; it just isn't that type of place. The Cock Horse is for sentimental its who like to dream of bygone days when the anvil and hammer changed and the oft-chanted poem was brewing in Longfellow's mind. But the food is every bit as good as the atmosphere.