/summon Item ~ ~3 ~ 
{
    Riding: 
    {
        Riding: 
        {
            id:"FallingSand",
            Time: 1,
            TileID: 137,
            DropItem: 0,
            TileEntityData: 
            {
                Command: 
                "
                    /summon FallingSand ~ ~15 ~ 
                    {
                        Time: 1,
                        TileID: 72,
                        Data: 1,
                        DropItem: 0,
                        Riding: 
                        {
                            id:\"FallingSand\", 
                            TileID: 137,
                            Time: 1,
                            DropItem: 0,
                            TileEntityData: 
                            {
                                Command: \"/setblock ~ ~1 ~ air\"
                            },
                            Riding: 
                            {
                                id: \"FallingSand\",
                                Time: 1,
                                TileID: 137,
                                DropItem: 0,
                                Motion: [0.9,0.9,0],
                                TileEntityData: 
                                {
                                    Command:
                                    \"
                                        /summon Item ~ ~5 ~-1 
                                        {
                                            Riding: 
                                            {
                                                Riding: 
                                                {
                                                    id: \\"FallingSand\\",
                                                    Time: 1,
                                                    TileID: 137,
                                                    DropItem: 0,
                                                    TileEntityData: 
                                                    {
                                                        Command: 
                                                        \\"
                                                            /summon FallingSand ~ ~15 ~2 
                                                            {
                                                                TileID: 1,
                                                                Time: 1,
                                                                DropItem: 0,
                                                                Motion: [0.0,0.9,0.9]
                                                            }
                                                        \\"
                                                    }
                                                },
                                                TileID: 72,
                                                Time: 1,
                                                DropItem: 0,
                                                id: \\"FallingSand\\"
                                            },
                                            Item: 
                                            {
                                                id: 1,
                                                Damage: 0,
                                                Count: 1
                                            },
                                            Age:5979
                                        }
                                    \"
                                }
                            }
                        }
                    }
                "
            },
            DropItem: 0
        },
        id: "FallingSand", 
        Time: 1,
        TileID: 72,
        DropItem: 0
    },
    Item: 
    {
        id: 1,
        Damage: 0,
        Count: 1
    },
    Age:5979
}