MXPA98004192A - Game to stack a brick tower - Google Patents

Abstract

The present invention relates to one or more players constituting a collapsible tower of individual bricks. At least two types of bricks are used to build the tower, with the two types of bricks (for example, square bricks and rectangular bricks) that have different physical characteristics that interact to affect the tower's stability and / or ease with the which can be removed a particular brick. Each layer of the tower can be formed of bricks having possibly similar physical properties, with at least two adjacent layers of the tower being formed of different shapes, sizes, and / or numbers of bricks. Different physical properties can also include weight, surface configuration and / or coefficient of friction, thus making it easy or more difficult to eliminate certain types of bricks that have a particular spatial relationship in the tower with respect to the other types of bricks. Two or more types of bricks can be packed to build a tower as a self-contained tower construction game, or a series of non-rectangular bricks can be used to complement an existing series of conventional rectangular bricks to build a tower, thus providing an appearance of improved play at a minimal expense. The brick tower can be built on a turntable to improve each player's access to all sides of the tower and / or to limit the time for each player to make their move, and the table is preferably provided with one level to provide a level base for the construction of the tor

Description

GAME TO STACK A TOWER OF BRICKS TECHNICAL FIELD The invention relates generally to games of skill, and more particularly to a game in which one or more players build a collapsible tower from individual bricks.

PREVIOUS TECHNIQUE Tower construction games are known in which a number of rectangular bricks are placed in layers to form a tower, with the orientation of the rectangular bricks alternating from one layer to another to provide frictional coupling between adjacent layers and bricks in the same layer. During a typical game scenario, the height of the tower is increased by removing bricks from one or more lower layers to build successive upper layers. A brick is a key brick if it is directly below the center of gravity of the bricks above it and is (or will be) the only brick in a given layer, or if it is one of the two remaining blocks on each side of the center gravity of the bricks on this. The game ends if the tower collapses because the key brick has been removed or, if the tower becomes unstable or is hit during the intended removal of any brick. Since there may be slight variations in the thickness of the individual bricks or the tower may not be exactly vertical. • the weight of the upper layers may not be evenly distributed in all the bricks of a given layer. Accordingly, even a brick that is not a key brick can be bearing much of the weight of the tower in which case one or more bricks in adjacent layers will be dragged out of position by friction when the weight bearing brick is removed. Therefore, it is conventional to allow players to try loose bricks before deciding which bricks to remove, but restricting players to the use of only one hand # while removing the bricks. An example of such a game using precisely manufactured polished wooden bricks is sold under the J ENGA brand of Milton Bradley Company. A known variant sold in Canada under the brand J ENGA ULTIMATE uses more than one rectangular brick color, with the different colors randomly distributed through the original tower.

Roll a dice to determine which brick color should be removed during the next round of the game, adding an element of opportunity for the start of the game. Although the described games use bricks that have length-to-width ratio of approximately 3: 1, so three bricks can initially be placed in a compact square layer having three contiguous bricks, similar tower construction sets are known in which somewhat narrower rectangular blocks are initially spaced apart horizontally. Other known variants use rectangular plastic bricks.

DESCRIPTION OF THE INVENTION The present invention improves the game attraction of the known tower building games by providing additional and alternative variants requiring different levels of manual dexterity and / or different strategies, thereby providing game attraction for different kinds of players. In accordance with a general aspect of the invention, at least two types of bricks are used to construct the tower, with the two types of bricks having different physical characteristics interacting to affect the stability of the tower and / or ease with which can be removed a particular brick. According to a first specific aspect of the invention, each layer of the tower is formed from bricks possibly having similar physical properties, although at least two adjacent layers of the tower are formed from bricks of different shapes, sizes and / or numbers. According to a second specific aspect of the invention, different physical properties include weight, surface configuration and / or coefficient of friction, making it easier or more difficult in this way to remove certain types of bricks that have a particular spatial relationship in the tower with respect to others types of bricks. According to a third specific aspect of the invention, the shapes, sizes and / or other physical characteristics of various types of # bricks affect the ease with which certain bricks can be handled. According to a fourth specific aspect of the invention, the shapes of the different types of bricks are such that the bricks adjacent of a first type in a first layer can be frictionally coupled by a second type of brick in a second adjacent layer, although none of the bricks of the second layer is _ coupled by the bricks in the first layer. In accordance with a fifth specific aspect of the invention, the sizes or shapes of at least some of the bricks is such that a single layer can have at least three key bricks, the removal of any one of them would result in the collapse of the tower. As currently contemplated, two or more types of tower construction bricks can be packaged as a construction game of self-contained tower, or a set of non-rectangular bricks can be used to complement an existing set of conventional rectangular tower building bricks, thereby providing enhanced play attraction at minimal cost. According to another aspect of the invention, the brick tower is built on a turntable to improve the access of each player to all sides of the tower and / or limit the time of each player to make his movement and the table Rotary is preferably provided with a level to provide a level base for the construction of the tower.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a tower construction set of the prior art using a simple size and shape of rectangular bricks. Fig. 2 is a plan view of the tower of Fig. 1 showing how a single layer comprises a side-by-side arrangement of three rectangular bricks. Fig. 3 shows a variant of the tower of Fig. 1 where a space is provided between the adjacent bricks. Fig. 4 shows a first embodiment of the present invention, in which a composite tower incorporates a layer of square bricks surrounded from above and below by respective crossed layers of rectangular bricks, wherein all the bricks have the same width. Fig. 5 is a plan view showing how a single layer of the composite tower of Fig. 4 may contain only square bricks. Fig. 6 is a plan view of a single layer of a variant of the composite tower of fig. 4, which shows how a single layer can contain two or more brick shapes. Fig. 7 shows a first variation of the tower composed of the Fig. 4 where the widths of the two types of bricks is not the same and all the bricks are packed closely together. Fig. 8 is a plan view of a second variation of the composite tower of Fig. 4, where the widths of two types of bricks is not the same and at least the narrowest bricks are loose packed. Fig. 9 is a plan view of two adjacent layers in a third variation of the set of Fig. 4, where the widths of two types of bricks is not the same, but the number of narrower bricks increases from so that the narrowest bricks occupy in the aggregate approximately the same area as the widest bricks. Fig. 10 shows another embodiment in which at least some of the rectangular bricks are supported on a relatively small horizontal surface of bricks having a non-rectangular cross section in a vertical plane, with the two brick forms having different properties physical Fig. 1 1 shows a variant of the embodiment of Fig. 10 in which the square bricks are supported on the relatively horizontal horizontal surface of the bricks having a non-rectangular cross section in a vertical plane. Fig. 12 shows a second variant of the embodiment of Fig. 10 that uses two types of bricks each having a different non-rectangular section. Fig. 13 shows a third embodiment of the present invention wherein at least some of the bricks have a non-rectangular cross section in a horizontal plane. Figure 14 shows a variant of the embodiment of fig 1 3 where the bricks having a non-rectangular cross section are closely packed together in an intertrawn arrangement in which the bricks of the adjacent layers are oriented in different directions. Figure 15 shows another variant plus that has two types of 5 rectangular bricks, with the height of the first type of brick that is an integral multiple of the height of the second type of brick. Figure 16 shows a tower construction game in which the tower is constructed on a rotating table having an integrated level.

BEST WAY TO CARRY OUT THE I NVENTION Referring to Fig. 1, which shows a single player 1 playing a conventional tower construction game such as the J ENGA game mentioned above, it can be seen that the tower of the technique above 2 is formed in a conventional manner from layers 3 of rectangular bricks 4. Each rectangular brick of the prior art 4 has the same height H, and (as best seen in the plan view of Fig. 2) a width W equal to precisely one third of its length L, so that three contiguous blocks 4A, 4B, 4C form a layer square 3 having a vertical dimension of H and a horizontal dimension of L = 3W. Referring again to Fig. 1 a number of rectangular bricks 4 are initially placed in layers 3A 3B, 3C 3R to form the tower 2, with the orientation of the rectangular bricks 4 in a first layer 3A that is perpendicular to that in a second adjacent layer 3B to provide mechanical intertrabado (frictional coupling) between the individual bricks of two crossed layers. During play, the height of the tower is increased by removing the blocks from one or more lower layers 3F, 31, 3N, 3T, 3Q to successively build upper layers 3S, 3T, 3U, 3V. A brick is a key brick if it is directly below the center of gravity of the bricks above it and is (or will be) the only brick in a given layer (for example the simple key brick 6), or if it is one of two remaining bricks on either side of the center of gravity of the bricks above it (for example, the pair of key bricks, 6A, 6B). The game ends if the tower 2 becomes unstable and collapses due to the removal of a key brick 6A, 6B, or if the tower collapses during the intended removal of any brick 4. Since there may be slight variations in thickness H and the surface characteristics of the individual bricks 4 and, since the tower 2 may not be exactly vertical, the weight of the layers 3G, 3H, 31, 3M may not be evenly distributed on all the bricks 4 of a given layer 3. Consequently, it is possible to allow players 1 to try loose bricks 5 (which can be easily removed) or key bricks 6 (which can not be removed) before deciding which brick to remove. An example of such a game using precisely manufactured polished wooden bricks is the J ENGA game mentioned above. Fig. 3 shows a known variant using modified rectangular bricks 4 'having a width W significantly less than 1/3 of its length L' to thereby provide a space between adjacent bricks 4 'of the same layer 3. horizontal separation facilitates the removal of a central brick 4'A eliminating any possibility of contact with the two external bricks 4'B, 4'C during the removal process. It should be evident then that a second variant is possible (not illustrated) that incorporates wider bricks of Fig. 1 with the separate arrangement of Fig. 4, placing each brick on its shorter edge. Since the stability is generally improved with a relatively lower center of gravity on a relatively wide base, the stacking of each stack at its shorter edge will result in a taller but less stable tower for a given number of bricks. As previously mentioned, the JENGA U LTIMATE variant of the game described above J ENGA uses bricks of different colors, while other tower construction sets differ from the original J ENGA game in that they use rectangular bricks of different dimensions and / or different materials. However, in accordance with one aspect of the present invention and as illustrated in FIG. 4, any of the known tower construction sets can be made more interesting and more challenging by using two or more brick shapes and / or sizes. which include for example not only rectangular bricks 4 but also square bricks 7 for building a composite tower 10, preferably with each layer 3, 3 'which is constructed only from a brick form 4, 7 as shown in FIG. 4 and Fig. 5, but with different forms of bricks that are used to build different layers. Alternatively, as shown in Fig. 6, the square bricks 7 and rectangular 4, 4 'may be combined in a single layer 3. Those skilled in the art will realize that the maximum mechanical cross-cutting between the cross-layers will result if the tower 2 is constructed only of rectangular bricks as shown in Fig. 2, with each rectangular brick 4 being sufficiently long that it extends from one side 8 to the other side 9 of the tower 2. Replacing one of the bricks rectangular 4 with two or more square bricks 7 is reduced but the frictional cross-coupling between the cross-layers is not completely eliminated, resulting in a somewhat less stable tower that is more sensitive to off-level conditions and requires greater dexterity for construction. Accordingly, the mode of Fig. 4 represents a marked improvement in the game value over the known games illustrated in Fig. 1 and Fig. 3. Assuming that the rules of the game allow the use of only one hand, and they do not allow the simultaneous removal of more than one brick or the sliding of a brick in a position previously occupied by a second brick, it will be evident that if a single layer contains nine square bricks 7 packed tightly in a 3 x 3 box as As illustrated in FIG. 5, at least one corner brick 7A must be removed before the player can grasp an average brick 7B and at least two medium bricks 7B must be removed before the player can obtain a brick. hold on the brick central 7C.

The combination of different brick shapes 4, 7 is also added to the strategic aspects of the game, because the stability of the composite tower 10 constructed from two or more types of brick 4, 7, is affected not only by the levels 3A, 3B, ..., 3M in which two types of bricks are placed, but also by how the rectangular bricks 4 are oriented on and under the square bricks 7 with respect to each other. For example, a somewhat more stable structure will result if, as shown in Fig. 4 and Fig. 7, the layer of rectangular bricks on the layer with the square bricks is oriented with its main axis perpendicular to that of the layer of rectangular bricks under the layer of square bricks, with square bricks that serve to couple the interlocking forces between two layers oriented perpendicularly separated from rectangular bricks. Furthermore, as is clear from an inspection of Fig. 5, the combinations not only of a brick (for example the central brick 7C) or two bricks (for example, two medium bricks 7B in a row or middle column placed for supporting an individual key rectangular brick on that middle row or column, but also four corner bricks 7A or two medium bricks 7B placed on two key rectangular bricks on two rows or external columns, can function as key bricks in a given layer of nine In addition, it is not essential (unless rules provide) that all nine square bricks should be placed squarely in a square bricks layer before any rectangular bricks can be placed in the next layer, but only that which includes one or more key bricks placed to support the key bricks in the next layer Fig. 6 is a plan view of another variant of the composite tower embodiment of Fig. 4 in which an individual layer may contain two or more brick shapes 4, 7, 4 ', thus adding to the strategy and skill required to play the game. In addition, although two or more bricks of the same size and shape may have different weights, in which case the removal of a heavy external brick will more likely cause an unbalanced twist and possible tower wobble than the removal of a lighter brick. in the same location. Fig. 7 shows another embodiment of the present invention in which the different bricks 4, 7 'vary in size (width) as well as in shape (square to rectangle) although each layer consists of only one type of brick in a narrow configuration packed, resulting therefore in an orientation superimposed between the bricks of adjacent layers. As shown in Fig. 8, some or all of the narrow square bricks 7 'of Fig. 7 can be separated horizontally from each other similar to the separate construction shown in Fig. 3. By loosely combining the packed layers of the narrower bricks 7 'with the more closely packed layers of wider rectangular bricks 4, each square brick 7' will be in full contact with only one rectangular brick 4 on and only one brick rectangular below this. In such a configuration, a rectangular brick \\ W 4 can be removed only in case we are the lower support of a square brick; however, a single square brick 7 'can support a rectangular brick, which can in turn be cantilevered by the weight of additional upper layers. In addition, 5 due to the loose space between the square bricks 7 ', in contrast to the tightly packed configurations of Fig. 5 and Fig. 7, it is possible to pull a middle brick 7B without first removing any of the four corner bricks 7A. Therefore it will be appreciated that not only the % appearance but also the game attraction of the modality of Fig. 8 are further improved by making two types of bricks of different widths. Fig. 8 also illustrates that two corner bricks 7"A and a middle brick 7" B can be key bricks. To further facilitate the removal of an average brick 7"B, at least some of the square bricks 7 'may be made of a ferrous material or provided with holes key or other means to attach a magnetized or properly configured removal tool. Fig. 9 shows another variant of the modalities of Figs. 7 & 8 in which the number of smaller square bricks 7 'is increased to ten and six so that the bricks, smaller occupy in the added approximately the same area as the nine square bricks 7 of the embodiment of Fig. 8. In that case there will be an overlapped placement between two widths of the bricks 4. 7 'which provides frictional engagement even between the square bricks 7'. thus providing additional stability, which in turn further complicates the strategy of determining which of the bricks 4, 7 'can be removed safely. Reference should now be made to Fig. 10, which shows a third embodiment of the present invention in which at least some of the bricks 1 1 have a hexagonal or a non-rectangular cross section in a vertical plane! transverse to the longitudinal axis of the brick, with the hexagonal bricks 1 1 used to replace some or all of the layers of rectangular bricks 4 in the prior art 2, 2 'of the modalities of Fig. 1 and Fig. 3. Observe what in the embodiment illustrated, some layers 3"contain both types of bricks 4, 11, while other layers 3, 3 'each contain a type of brick, as will be clear from the description of the different variants of tower 10, 1 1 &12, hexagonal bricks 1 1 provide only a line contact between adjacent bricks of the same layer thereby combining the advantages of the tightly packed arrangement of Fig. 1 (the precise alignment of the individual bricks) and the separate arrangement of Fig. 3 (easy to remove). Those with experience in the art will realize that a reduced contact area between adjacent bricks at the same level can also be achieved with other non-rectangular vertical profiles, or a combination of rectangular and non-rectangular profiles. The two types of brick 1 1, 4 can be formed from different materials having different coefficients of friction, which will further emphasize the variations in touch sensation resulting from the different sizes of the contact area between the different sizes and shapes of bricks.

In Fig. 11, at least some of the elongated bricks 11 have a relatively horizontal surface supporting the square bricks 7 '. When orienting the hexagon with two parallel flat surfaces 12, 13 in the upper and lower part, each side 14 will not be vertical, although it will have a projecting center 15 which keeps the upper and lower part 12, 13 in a separate relation, even if two adjacent bricks 1 1 touch each other at their center 15, thereby combining the less stable (and therefore more challenging) aspects of the separate configuration of Fig. 7 with aspects of self-alignment of the closely spaced configuration of Fig. 1. Such a form of construction combines the advantages of separate square bricks. narrows of the embodiment of Fig. 8 (for example, greater accessibility of the middle bricks) with the advantage of maintaining at least a small contact area between adjacent blocks in the same layer (self-separation), to provide an especially challenging and aesthetically pleasing game. Fig. 12 shows a tower variant constructed only of elongated bricks 1 1, 1 '' having a non-rectangular cross section in the plane transverse to the longitudinal axis of the brick. including one or more bricks 1 1 'having a circular cross section. Such circular bricks can still function as one of the two key bricks 1 1 A, 1 1 B; however it will be appreciated that if a given layer contains only circular bricks with parallel axes, the tower will be unstable. It will be appreciated that other combinations of vertical cross section are possible, for example square and triangular. provided all the bricks in the same layer that have the same height. Figs. 13 & 14 show embodiments in which at least some of the bricks have a non-rectangular cross section in the horizontal plane. In the embodiment of Fig. 13, the non-rectangular cross section is circular and the brick 16 is a vertical cylinder; in the embodiment of Fig. 14, it is a brick 16 'whose horizontal cross section is hexagonal. It should be evident that the other horizontal sections are also possible, including other shapes such as ovals, irregular polygons and other regular polygons. As previously mentioned, the stability is too large to measure a function of the ratio of height to width, it is also possible to change the difficulty of play, and / or to discourage or facilitate the construction of towers of a predetermined height and / or having a predetermined number of levels, by adjusting the height of the non-rectangular bricks 16, 16 '. Although such non-rectangular horizontal cross sections are some aspects similar to the square bricks in Fig. 4 and Fig. 7, in general they have the advantage that although adjacent bricks may be in contact with another (thus allowing the separation between the bricks to hold up to a value that corresponds to the fixed spacing of the rectangular bricks in the other layers), however, there is a protruding surface that can easily be held by the player without disturbing the other bricks. Another advantage of a brick having a non-rectangular cross section is the fact that it does not have a width and therefore, as such a brick is being removed, the change in its contact area with adjacent bricks is not a linear function of its displacement, which results in a non-linear touch feedback that is different from that associated with a linear change in the contact area produced by a rectangular brick that is displaced in the direction of its longitudinal axis. As shown in Fig. 15, some of the rectangular bricks 4"may be short that have a height H" than an integral fraction (for example one half) the height H "of a large prior art brick 4 ', so that a stacked combination of the first and second short bricks 4"can provide the same support as an individual large brick 4 ', although upon removal of the first short brick by a first player, the removal of the second short brick is trivial, what effect provides a free movement for the second player. Full and half-height brick combinations (or other integral fractions such as a third) are also possible with bricks having a non-rectangular cross-section, for example the hexagonal bricks 1 1 of Fig. 10. In addition to the shape and size, other physical aspects of some. although not necessarily of all, the bricks can be handled to further improve the attraction of play, without departing from the spirit of the present invention. For example, as indicated by different surface shading in Figs. 6, 7, 8, 9, 1 1 & 14, some bricks may have a different surface texture or configuration (for example, the coefficient of friction) than other bricks (or perhaps a non-linear coefficient of friction that is dependent on the load per unit area) resulting in greater probability that the removal of a non-key brick will cause unpredictable movement in the bricks in other layers. As in another example, some of the bricks could contain hidden magnets and / or be made of magnetic material, thus resulting in unpredictable non-gravitational forces between certain bricks (though not other bricks) which would be evident only when a brick apparently loose is removed. As # a third example, some of the bricks could be solid as long as others could be of a second type with a heavy or recessed center (preferably not visible to visual inspection), resulting in a greater displacement at the center of gravity when the heavier brick type is removed. Fig. 16 shows how the game attraction of the game Tower construction can be further improved by means of suitable accessories. In Fig. 16, the composite tower 1 0 is constructed on a rotary table 17, which can be rotated at a constant angular velocity by means of a clockwork or electric motor (not shown) similar to that found in an oven of microwave. This allows not only players to see the complete composite tower 10 from all angles, but also establishes a current period of time (eg, revolutions of one and a half) during which each player must make his move. Preferably, a level 18 can be incorporated within the rotary table 17, ensuring this so that the upper surface 1 9 of the turntable 1 7 is always horizontal and therefore that the towers 2, 2 ', 10 can always be maintained in a stable vertical position as they are rotated on the turntable 17. If the game is going to play outdoors in the sand or grass, stability can be improved by using a platform with legs, preferably provided with a rotating table similar to the rotary table 17 and a tape measuring rod to monitor the height of a tower just before it collapses. Similarly, if a game is played indoors, a felt mat or woven cloth can be used to catch falling bricks and to protect adjacent polished wood surfaces from being scratched or dented. If the carpet is to be used on a non-uniform surface such as tiles or mats, it can be provided with a cardboard or wood insert to provide a flat or level surface on which the tower is constructed.

Claims (10)

1 . A set for stacking a brick tower of the type including a horizontal prime layer (3) of n primary bricks (4) each having a rectangular horizontal cross-section defined by a predetermined length (L) and a first equal width (W) a or less than said predetermined length divided by n, wherein n is at least three; a secondary horizontal layer (3 ') of secondary bricks (7, 7') in the upper part of said primary layer, the aggregate surface area of the upper surfaces of all the primary bricks in the primary horizontal layer which is at least as large as the aggregate surface area of the top surfaces of all the secondary bricks in said secondary horizontal layer, and a plurality of additional horizontal layers (3 3 '), characterized in that the number of bricks in the secondary layer (nxn ) is greater than the number of bricks (n) in the primary layer, and at least one of the bricks in the secondary layer (3 ') is a square brick (7, 7') having a horizontal cross section defined by a second predetermined width equal to or less than said first predetermined width (W) and having a fixed relation to said first predetermined width.

2. The game for stacking a brick tower of claim 1, further characterized in that the secondary layer (3 ') includes at least n x n of said square bricks (7, 7').

3. The invention of claim 1, further characterized in that each of the primary bricks has a respective lower height than said first predetermined width. The invention of claim 1, further characterized in that n is equal to 3. The invention of claim 1, further characterized in that the aggregate surface area of the top surfaces of all the bricks (4) in the Primary layer (3) substantially equals the aggregate surface area of the top surfaces of all bricks (4, 4", 7) in the secondary layer (3 ', 3"). 6. The invention of claim 1, further characterized in that the sum of the surface areas of the upper surfaces of each of the bricks (4) in the primary layer (3) exceeds that the sum of the surface areas of the upper surfaces of the bricks (7 ') in the secondary layer (3'). 7. The invention of claim 1, further characterized in that the edges of the upper surface of each of the bricks (4, 7, 7 ', 4") are formed of vertical lines 8. The invention of claim 7, further characterized in that all the bricks in the secondary layer are the square bricks (7, 7 ') - 9. The invention of claim 7, characterized moreover, the width (W) of a brick (4) in the primary layer (3) is substantially equal to the width (W) of a brick (7) in the secondary layer (3 '). claim 1, further characterized in that at least some of the bricks have a non-rectangular, vertical cross-section (11, 11 ') .1 A method for playing a game for stacking a brick tower with a plurality of rectangular bricks all having a first equal width and a first length equal at least three times to the same first width and a plurality of short bricks all having the same second width and the same second length, the second length being substantially equal to follow nda width and smaller than the first length, comprising the steps: building a first primary layer of exactly n rectangular bricks oriented in a first direction; building a secondary layer of more than n bricks at the top of said first primary layer, the secondary layer including at least two short bricks; construct a second primary layer of exactly n rectangular bricks oriented in a second direction perpendicular to the first direction in the upper part of said first secondary layer; remove a rectangular brick from said layers; placing the rectangular brick removed at the top of said second primary layer to initiate a third primary layer on said second primary layer with the rectangular brick removed oriented in said first direction, remove one of the short bricks from the secondary layer, and place the short brick removed at the top of the third 5 primary layer to start a second secondary layer in this way. The method of claim 1, wherein before the construction of the third primary layer and the second secondary layer, each of the rectangular bricks in the first primary layer • Supports exactly n secondary bricks in the first layer 10 secondary bricks, and each of the primary bricks in the second primary layer is supported only by n secondary bricks in the first secondary layer. The method of claim 1, wherein before the construction of the third primary layer and the second secondary layer, 15 each of the n rectangular bricks in the first primary layer supports more than n short bricks in the first secondary layer, and each of the n rectangular bricks in the second primary layer is supported by more than n short bricks in the first secondary layer. The method of claim 1, wherein the secondary bricks 20 are closely packed together. 15. The method of claim 1, wherein the secondary bricks are packed together loosely. The method of claim 1, wherein the first secondary layer comprises four corner bricks, at least four middle bricks and at least one central brick, and each central brick is surrounded by four middle bricks. 17. The method of claim 1, wherein the short bricks have a non-rectangular horizontal cross section. 18. The method of claim 1, wherein the bricks have a square horizontal cross section. 19. The method of claim 1, wherein the first width is equal to said second width.