JUST AFTER the voice of the last 1973 Commencement speaker had faded away, construction workers began tearing down Hunt Hall and blasting a 40-foot-deep hole in front of Lamont Library to make way for the first new buildings in the Yard since Lamont was built in 1949.

This summer, as in summers before, large numbers of Summer School students will reside in the Yard. But this summer, Yard residents will delight to the thunder of wrecking expeditions, and the Yard that bore grass for Commencement--one of the only such green spots on the Harvard campus--will transform itself into a less pleasing mud and dust landscape.

The two new buildings--a freshman dormitory and the Nathan M. Pusey Library--are both being built to relieve overcrowded conditions.

The 2.5 to 1 male-female ratio that President Bok announced two years ago has resulted in an increase of about 300 students. The new dorm, which will be called Canaday Hall after Ward M. Canaday '07, the Toledo, Ohio oil magnate who donated the $3 million building fee, will lessen the crowded housing conditions in the Yard and the Houses.

The Pusey Library will house 2 million books that are now jammed into Widener, Houghton and Lamont Libraries.

Both buildings have aroused a tremendous amount of concern about the sacrosanct architectural environment of the Yard. In both cases, release of the building plans was delayed--the new dorm will start to go up over the summer even though its design has not yet been made public--because of a series of last-minute reviews of details.

It seems strange, in the year after Gund Hall and the Science Center were completed, to hear things like, "The thing that is the greatest concern is that the color of the building material and the texture of the material harmonize with the rest of the Yard," which is what Harold L. Goyette, the director of the Planning Office, says about the new dorm.

Harvard's builders are tired of the jumble of styles that most construction here in the sixties brought on, and, above all, they do not want to disrupt the Yard with a building that seems out of place.

Cambridge architects Hugh Stubbins and Associates, who designed the Pusey Library, avoided the problem of conforming to the architecture of the Yard by putting the library almost completely underground. The Pusey Library will have three levels but will rise only nine feet above ground level. The library's roof will be covered with grass, shrubs and a walkway, and a grassy surrounding mound will shield it from view, so that it will look more foliated than the dusty open space between Houghton and Lamont that it will replace.

The $8-million library is designed with future expansion in mind. The first phase will be completed by Spring 1975, and its size can, if necessary, be doubled afterwards through further underground construction. And Bok could tear down the former President's House at 17 Quincy Street--now the Corporation offices--and build an aboveground wing of the library. He says that possibility "won't come up for a long time--1975 or 1980--and we hope that by that time new technology in the area of miniaturizing archives will have made further expansion of the library unnecessary."

No new books will go into the Pusey Library. It will house only overflow--the University Archives, the map collection, the theater collection and about one-million other miscellaneous books--from Widener, Houghton and Lamont. Underground passageways will connect the Pusey Library to the surrounding libraries to make transfer of books easier.

The Library will be open only to graduate students, Faculty members and other people who need to use its special collections; anyone else who tries to enter will be turned away by a guard at the door.

THE PLANNING of the Pusey Library has proceeded fairly smoothly, although there have been a few complaints about its unorthodox appearance. The new freshman dorm, however, has been plagued by controversy. The Visual and Environmental Studies Department, the Faculty Council and many people living at Radcliffe have all expressed their disapproval of some aspect of the new dorm.

As early as last November, it was rumored that Bok had a donor all lined up for the new dorm. But there was apparently one problem with the arrangement: Bok and Radcliffe President Horner wanted the dorm to be built at Radcliffe, most probably as a series of additions to South House, and the donor refused to have it anywhere but the Yard. The matter must still have been in doubt by late January, because a series of blueprints for construction at Radcliffe--in the form of connecting wings between existing Quad dorms--was drawn up and posted at South House. The South House Committee gave the plans its enthusiastic approval in February, only to be told by Martin H. Peretz, Master of South House, that there was no money available for new construction at Radcliffe.

On March 22, Bok announced that the new dorm would be built on the site of Hunt Hall, that it would be no more than five stories tall and would house about 240 students and their proctors. Bok said that the dorm would be completed by September 1974, and that the Visual and Environmental Studies Department, which is now located in Hunt Hall, would move to Sever Hall.