In front of the Teacher's Platform, and facing it, arranged in a semi-circular form, as shown at q qq, in the Plan of the Second Story, are the Seats for the scholars. These are comfortable and convenient Arm-chairs, of which the annexed diagram shows the form. Each has a rack at the side (A) for convenience in holding the books or slates of the scholars. These chairs were the contrivance of Mr. Ingraham, and were introduced by him into the Primary Schools, in 1842, since which time, the Primary School Board have recommended their introduction into all their schools, in preference to any other seats, and about one hundred and thirty of the one hundred and sixty schools are now supplied with them. They are not fastened to the floor, but can be moved whenever necessary; and this is found to be a great convenience, and productive of no disadvantage. They have been strongly recommended by the Committees on School and Philosophical Apparatus, at the Exhibitions of the Massachusetts Charitable Mechanics' Association, in 1844 and 1847, and premiums were awarded for them in both those years.

The following diagram is an elevation of the Front wall of the Schoolroom, as seen from the Teacher's Platform. It is on the same scale with the preceding Plan of the Second Story,-eight feet to the inch.

Each Schoolroom is lighted by four windows; and in the central pier, between the windows, are the Cold-air and Chimney Flues, or the Furnace Flues. The Fire-place, or Furnace Flue, is represented at F, as in the preceding Plans of the different Stories. The arrangement of the Flues, in this pier, will be seen in the next diagram.

On the mantel-piece, over the Furnace Flue, is, in one room, a Vase of Na. tive Grasses, or Flowers, and in the others, ornamental Statues, or Statuettes, furnished by the Teachers. Above this, suspended on the pier, is the Clock.

Between the other windows, are Cabinets, for the reception of Minerals, Shells, and other objects of Natural History or Curiosity. Their location is seen at u u, in the Plans of the respective Stories. There are two of these Cabinets in each Schoolroom, between the windows, above the skirting, and as high as the windows, with double sash-doors, of cherry-wood, hung with brass hinges, fastened with thumb-slides and locks, and fitted with rosewood knobs. There are twelve shelves in each, six of them being inclined, with narrow ledges on each, to prevent the specimens from rolling off. Immediately below them are small Closets, with four shelves in each, and double doors, hung and fastened in the same manner as the sash doors.

The Blinds of the Second Story, represented in this diagram, are framed, two parts to each window, and are hung with weights and pulleys, in the same manner as the window sashes. They run up above the tops of the windows, and behind the skirting of the next story above, in close boxes, and

have rings on the bottom rails, to draw them down. In this elevation, they are shown in different positions. The windows in the First Story are fitted with Venetian Blinds, and those in the Third Story with Inside Shutter-Blinds. All the window-stools are wide, and contain Vases of Native Grasses, or Flowers.

Particular attention has been given to the mode of Heating and Ventilating these buildings; and provision has been made for a copious and constant supply of fresh air, from out-of-doors, which is so introduced, that it is sufficiently warmed before it enters the Schoolrooms.

The Sheafe-street building is heated by one of Chilson's largest-sized Furaces, though it was originally constructed with a view to using Dr. Clark's excellent Ventilating Stoves, as in the other two buildings.*

The accompanying diagram shows the arrangement of the Cold-air and Smoke Flues, as arranged for the Stoves. It will be well to examine it in connection with the transversesectional elevation, (p. 184,) and the Floor Plans of the different Stories, (pp. 177, 179, 180.)

1, 2, 3, Floorings of the First, Second, and Third Stories. 4, Roof.

CA, Cold-air Flue for First Story, which delivers the air from without, under the Stove, as shown at C A, in the transverse-section, (p. 184,) and at F, in the floor-plans.

r, r, Cold-air Flue for Second Story, which empties into the box under the Stove, at CA, in the Second Story of the transverse-sectional elevation. It corresponds to r, in the Floor Plans of the first and second stories.

t, t, Cold-air Flue for Third Story, which empties into the box CA, under the Stove of that Story, as seen in the transverse-sectional elevation, and at F, in the Floor Plan. It corresponds to t, in the Floor Plans.

These Cold-air Ducts are twelve by eighteen inches, inside, and are smoothly plastered, throughout. This is hardly large enough, however.

s, s, Smoke Flues. That of First Story corresponds to s, in the floor plan of first story, and to r, in those of the second and third. That of Second Story corresponds to s, in second-story Plan, and to t, in third-story Plan. That of Third Story corresponds to s, on the Plan of that Story.

These Smoke Flues are eight inches square, in2 side, and are smoothly plastered, throughout. That of each Story commences in the centre of the pier in the room to which it belongs.

[The pier in which these Cold-air Ducts and Smoke Flues are placed, is wider than the piers between the other windows, in order to allow sufficient width to the Ducts. It must be at least six feet.]

It will be seen, from the transverse-sectional elevation, (p. 184,) (the Smoke Flue in which is represented as continuous, it not being practicable to show the bends,) as well as from the Plans of each Story, that the arrangements for Ventilation are directly opposite the Chimney Flues. The Ventiducts are contained in the projecting pier back of the Teachers' Platforms and Tables shown at l, m, in the Floor Plans.

It has already been stated, that particular attention has been paid to the * Descriptions and Plans of this Furnace and Stove will be found on page 148.

mode of Ventilation; and it is believed that the system, if not perfect, is better adapted to its purpose than any other. The Ventiduct for each room is of sufficient size for the room; and the three are arranged as shown in the next diagram. It will be seen, that the Ventiduct for each room is in the centre of the pier, thus avoiding any unsymmetrical or one-sided (and of course unsightly) appearance.

1, 2, 3, 4, Floorings of the First, Second, and Third Stories, and Attic.

5, Roof.

c, c, c, Ventiduct of First Story, commencing in the centre of the pier. Between the ceiling of this room and the floor of the Second Story, this flue is turned to the left, and then continues in a straight line to the Attic, where it contracts and empties into the Ventilator V, on the Roof.

d, d, d, Ventiduct of Second Story, also commencing in the centre of the pier, and turning to the right, between the ceiling of the Second and floor of the Third Story, whence it is continued to the Attic, and empties into the Ventilator V.

e, e, Ventiduct of Third Story, also emptying into V.

These Ventiducts are made of thoroughly seasoned pine boards, smooth on the inside, and put together with two-inch screws. Each, as will be seen, is placed in the centre of the room to which it belongs. They are kept entirely separate from each other, through their whole length, from their bases to the point where they are discharged into the Ventilators on the Roof. Each is sixteen inches square inside, through its whole length to the Attic. where, as will be seen by the diagram, each is made narrower as it approaches its termination, till it is only eight inches in width, on the front, the three together measuring twenty five inches, the diameter of the base of the Ventilator on the roof. they are contracted, however, in this direction, they are gradually enlarged from back to front, so that each is increased from sixteen to twenty-four inches, the three together then forming a square of twentyfive inches, and fitting the base of the Ventilator into which they are discharged. The increase in this direction will be better seen in the Elevation on p. 184, where V V represents one Ventiduct, continued from the lower floor to the Ventilator.

As

V, Ventilator, on the Roof, into which the three Ventiducts from the schoolrooms are discharged. This is twenty-five inches in diameter.*

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v, v, Registers, to regulate the draught of air through the Ventiducts. There are two of these in each Ventiduct, one at the bottom, to carry off the lower and heavier stratum of foul air, which always settles near the floor; and the other near the ceiling of the room, for the escape of the lighter impure air, which ascends with the heat to the top of the room. Each of these Registers has a swivelblind, fitted with a stay-rod, and may be easily opened or closed by the Teacher.

o, o, Closets. The Ventiduct of each Story being in the centre of the projecting pier, affords room for Closets, on each side in the First Story, and on one side in the Second Story, as shown at oo. There are four in the First Story, two above and two below the wainscot. In the Second Story, there are two only, one above and the other below the wainscot; the other side of the pier being occupied by the Ventiduct of the First Story. In the Third Story there are of course none.

This plan of arranging the Heating and Ventilating apparatus has been adopted by the Committee on Ventilation of the Grammar School Board;* but as their plans and diagrams were taken from Mr. Ingraham's first draughts, before his final arrangement was decided upon, they are not so complete as these.

The preceding diagram gives a transverse-sectional elevation of the building. It has already been stated, that the children are seated with their backs to the light, and their faces towards the Teacher's Table and the wall above and on either side of it. On this wall, and also on the two end walls, (as shown in the transverse-section,) are suspended Maps, Charts, and Pictures, not only for ornament, but for the communication of instruction. Vases of Flowers and Native Grasses ornament the window-stools and the Teachers' Tables; and Statuettes and other useful ornaments and decorations are placed in various parts of the rooms so that whatever meets the eyes of the children is intended to convey useful and pleasing impressions, encouraging and gratifying the love of the beautiful, and combining the useful with the agreeable. The Cabinets of Minerals, Shells, and other objects of Natural History and Curiosity, add much to the interest and beauty of the rooms.

On the back wall, on either side of the Teacher's Platform, at SSSS, are four large Slates, in cherry-wood frames, each two and a half by four feet, used instead of Blackboards. These Slates are far preferable to the best Blackboards, and cost about the same as common ones. The Teachers greatly prefer them to Blackboards. In using them, slate pencils are of course employed, instead of chalk or crayons, and thus the dust and dirt of the chalk or crayons, which is not only disagreeable to the senses, but deleterious to health, by being drawn into the lungs,-are avoided. These Slates may be procured in Boston, of A. Wilbur.

Each School has convenient Recitation-rooms; though, in consequence of the space occupied by the stairs to the Second and Third Stories, the lower Story is not so conveniently accommodated, in this respect, as could be desired. It has, however, two good Entries, which are used for this purpose. In the Second and Third Stories, there are three of these rooms, of which much use is made. Their location is shown in the Floor Plans.

In these ante-rooms, are Closets for Brooms, Brushes, and other necessary articles of that description, and also Press-closets, furnished with shelves and brass clothes-hooks, for the Teachers' private use. In these, also, are Sinks, furnished with drawers and cupboards, pails, basins and ewers, mugs, &c. Pipes leading from the Sinks, convey the waste water into the Vaults; and in a short time, the waters of Lake Cochituate will be led into each Story. Each School has its own separate entrance; so that they will not interfere with each other. And each is provided with sufficient conveniences in its entry, for hanging the clothing of the pupils, thus avoiding the necessity of its ever being brought into the Schoolroom. Each has also two Umbrellastands in its entry.

In the Cellar, are placed the Furnace, and necessary conveniences attached to it, with Bins for coal and wood. Also two Rain-water Butts, one at each end, which receive all the water from the Roofs. Being connected with each other, by leaden pipes, under ground, the water in both stands at the same level; and a pipe, leading from the top of one of them into the Vault, prevents their ever running over.

The Cellar is paved with brick, and is convenient for a play-room, when the weather is too stormy for he children to go out of doors at recess-time Instead of having the usual out-door conveniences in the yard, they are here connected with the entries of the respective schoolrooms, so that no child has to go into the open air, except for play in recess-time, or to go