You are an expert at summarizing long articles. Proceed to summarize the following text:

You are an expert at summarizing long articles. Proceed to summarize the following text: 
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to window sashes and frames and, more particularly, to double-hung window sashes and frames therefor, which are constructed from (1) extruded parts that are composed of a plastic such as vinyl, and (2) milled or otherwise shaped parts that are composed of another material such as wood. 
     2. The Prior Art 
     A need has developed for window sash and frame assemblages that combine the advantages of (1) extruded construction components having the durability of a plastic material such as vinyl, and (2) milled or otherwise-shaped construction components having the esthetics of another material such as wood or an equivalent. It is desired that such assemblages be adapted for either new construction wherein ease of installation is an advantage, or old construction wherein out-of-plumb openings are common. 
     SUMMARY OF THE INVENTION 
     The primary object of the present invention is to provide a sash and frame assemblage for a window that is characterized by: (1) extruded plastic parts that feature a few interactive primary cross-sectional profiles, and (2) milled wood or otherwise-shaped parts that feature a secondary cross-sectional profile. The primary and secondary profiles coact simply, securely and attractively. The primary and secondary profiles, in cross-section, interactively feature a unique extrusion from which an entire sash is constructed, and a unique milled or otherwise-shaped facing which snaps precisely into secure engagement with such a sash. In addition to this unique extrusion, only a few auxiliary extrusions are needed. These auxiliary extrusions are specifically required for the forward and rearward meeting rails, and for out-of-plumb compensation. The frame of the present invention features extruded jambs that are pressed against the stiles of the window sashes by a resilient backing. 
     Other objects of the present invention will in part be obvious and will in part appear hereinafter. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a fuller understanding of the nature and objects of the present invention, reference is made to the following specification, which is to be read in reference to the accompanying drawing wherein: 
     FIG. 1 is a general front view of a window sash and frame assemblage, portions of which are designated by numerals in reference to details of the present invention that are displayed in the following figures; 
     FIG. 1A is a rear view of one of the window sashes of FIG. 1; 
     FIG. 2 is a broken-away cross-section of FIG. 1 in its entirety, taken along the line  2 — 2 ; 
     FIG. 3 is a broken-away cross-section of the jamb construction of FIG. 1, taken along the line  3 — 3 ; 
     FIG. 4 is a broken-away detail view of the top sash and bottom sash meeting rails, taken along the line  4 — 4  of FIG. 1; 
     FIG. 5 is a broken-away cross-sectional detail view of the adjustable sill assembly of FIG. 1, taken along the line  5 — 5 ; 
     FIG. 6 is an isolated cross-sectional view of the main sash extrusion of FIGS. 2 and 4; 
     FIG. 7 is an isolated cross-sectional view of the milled part of FIGS. 2 and 4; 
     FIG. 8 is an isolated cross-sectional view of the outer accessory meeting rail extrusion of FIGS. 2 and 4; 
     FIG. 9 is an isolated cross-sectional view of the inner accessory meeting rail extrusion of FIGS. 2 and 4; 
     FIG. 10 is an isolated cross-sectional view of the upper out-of-plumb adjustment extrusion of FIG. 2; and 
     FIG. 11 is an isolated cross-sectional view of the lower out-of-plumb adjustment extrusion of FIG.  2 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The assemblage illustrated in FIG. 1 comprises a frame  20 , an upper window sash  22 , and a lower window sash  24 . Frame  20  includes a header portion  26 , a sill portion  28 , and jamb portions  30  and  32 . Upper sash  22  includes a top rail  34 , an outer or forward meeting rail  36 , and a pair of stiles  38  and  40 , which hold a double glass pane  42 . Lower sash  24  includes an inner or rearward meeting rail  46 , a bottom rail  48 , and a pair of stiles  50  and  52 , which hold a double glass pane  54 . 
     In the illustrated embodiment, the aforementioned components are described as being constructed of vinyl polymer extrusions and milled wood or otherwise-shaped parts. The polymer extrusions, in an alternative form, may be composed of a polymer other than vinyl. The otherwise shaped parts, in an alternative form, may be composed of an extruded polymer such as vinyl. 
     The components of upper sash  22 , as indicated above, include top rail  34 , outer or forward meeting rail  36  and stiles  38 ,  40 . Each of these components includes an extrusion  35  as is well shown in FIG. 6 and a milled wood part  37  as is well shown in FIG.  7 . The components of lower sash  24 , as indicated above, include an inner or rearward meeting rail  46 , a bottom rail  48 , and a pair of stiles  50  and  52 . Each of these components includes an extrusion  53  as is well shown in FIG. 6 and a milled wood part  55  as is well shown in FIG.  7 . It will be observed that extrusions  35  and  53  are identical, and that milled parts  37  and  55  are identical. 
     The cross-section of FIG. 6, as generally shown at  57 , includes a hollow, rectangular base  56 , which consists of parallel longitudinal sections  56   a  and  56   b , and parallel transverse sections  56   c  and  56   d . Projecting from outer longitudinal section  56   a  is an inwardly bent finger  58 , which abuts against window pane  42 . Projecting from the inner and outer longitudinal sections  56   a  and  56   b  of base  56  is a groove  60  for a purpose to be described below. Projecting oppositely from the inner and outer transverse sections  56   c  and  56   d  of base  56  are a pair of oppositely directed elongated hooks  62 , 64  for a purpose now to be described. 
     The cross-section of FIG. 7 includes a body  66  having an extended face portion  68  and a restricted catch portion  70 . Catch portion  70  is provided with oppositely directed hooks  72 ,  74  that are designed to snap into engagement with oppositely directed hooks  62 ,  64  of the extrusion of FIG.  6 . By virtue of oppositely directed hooks  62 , 64  and oppositely directed hooks  72 , 74 , the vinyl extrusion and the milled wood part snap together into a snugly mated relationship. 
     As shown in FIG. 8, forward or outer meeting rail  36  includes an auxiliary extrusion  76  that has a base  78 , an extending bent finger  80  for engagement in the milled wood part, a catch  84  for retaining a felt or vinyl bulb strip  86 , a tongue  81  for reception by groove  60  of FIG. 6, and a projecting pinch finger  88 . 
     As indicated in FIG. 9, the inner or rearward meeting rail includes an auxiliary extrusion  89  that has a hollow rectangular base  90  for maintaining stability, a catch  92  for retaining a felt or vinyl bulb strip  93 , an extending finger  95  for engagement in a mating notch in the milled wood part, a tongue  91  for reception by groove  60  of FIG. 6, and an extending pinch finger  94 . 
     Out-of-plumb compensation is achieved by two extrusions, which are shown in detail at  96  and  98  in FIGS. 10 and 11. Lower extrusion  96 , in cross-section, includes a slanted base  100  that is adapted to rest on sill portion  28  of the window frame, a pair of legs  102 ,  104 , a pair of legs  106 ,  108 , each pair of which defines a channel, and a cross-piece  110  having a central opening that is adapted to receive a self-tapping adjusting screw. Upper extrusion  98 , in cross-section, includes a pair of legs  111 ,  112  and a pair of legs  114 ,  116 , each pair of which defines a channel, and a cross-piece  118  having a central opening that is adapted to receive a self-tapping adjusting screw. Such a screw is shown in FIG. 5 at  120 . The arrangement is such that the legs and channels of upper extrusion  98  and lower extrusion  96  engage each other adjustably and are locked in position by adjusting screws  120 , which enable plumb installation. 
     The frame  20  of the present invention, as shown in FIG. 3, features first and second extruded jambs that are sufficiently thin to be pressed against the stiles of the window sash by a resilient backing. As shown, each jamb consists of an outer accessory in the form of a vinyl extrusion  122  and an inner accessory in the form of a vinyl extrusion  124 . In cross-section, outer extrusion  122  consists of a channel, which is fastened to the jamb portion of the window frame and which presents oppositely directed hooks  126  and  128 . In cross-section, inner jamb accessory extrusion consists of two parallel sections,  130  and  132 , which provide guide rails along which the window stiles may slide. A resilient foam  134  is interposed between the outer and inner jamb accessories to press the outer jamb accessory tightly against the stiles of the sashes. 
     OPERATION 
     The operation of the illustrated assemblage of frame and sashes is as follows. A single extruded cross-section and a single milled cross-section provide the rails and stiles of the sashes with the trouble-free functionality of vinyl and the esthetic functionality of wood. A few accessory extruded cross-sections provide weather-proof meeting rails and jambs and out-of-plumb compensation. Assembly of the extruded and milled components is accomplished simply and securely. As shown in FIG. 1A, each sash is constructed from an assembly of the extrusions of FIG. 6, which are mitered and welded together at their ends.

Summary:
A single extruded cross-section and a single milled cross-section provide the rails and stiles of window sashes with the trouble-free functionality of vinyl and the esthetic functionality of wood. A few accessory extruded cross-sections provide weatherproof meeting rails and jambs and out-of-plumb compensation. Assembly of the extruded and milled components is accomplished simply and securely. This structure is characterized by plastic extrusions that feature a few interactive primary cross-sectional profiles, and milled wood or otherwise-shaped parts that feature a secondary cross-sectional profile. The primary and secondary profiles coact simply, securely and attractively.