Blackmore sewing patterns

 Emerging from a cupboard (not my own) - these 1950s (or 1960s) patterns -

with their succinct instructions on the back of the envelope (times were simpler then) -

and the pattern itself - no seam lines, no indication of what the piece was - just a notch here and there -

You had to know what you were doing before you started! 

The V&A lists a Blackmore pattern for a girl's gymslip (Used by Mrs Madeleine Ruben to make clothes for her daughters Claire (born 1953) and Isabelle (born 1956)) in its collection, and describes it in cataloguing language:

[Sewing pattern] Five pattern pieces for making a girl's gymslip, cut from cream-coloured tissue paper 

[Envelope] Rectangular envelope of portrait proportions, with a tuck-in flap at one end, to contain the pattern pieces. The envelope is of cream paper printed in black: the garment is illustrated in photogravure on the obverse, and the pattern layout and instructions for making up the garment on the reverse.

Blackmore was a British pattern company based in Bletchley, latterly Bletchley and London - one source says it was started about 1845 and published patterns till the 1940s. Other British pattern companies from the heyday of home sewing are Bestway, Weldons, Maudella, Practical Patterns, Odhams ... and many more. The Commercial Pattern Archive ("to recreate or date clothing from 1868 to 2000") is based at the University of Rhode Island.

This discussion raises the point that patterns from the 1940s, are rare survivals because many if not most people would make their own patterns by copying existing clothing, rather than buying paper patterns. 

Info on dating sewing patterns is here. Examples of 1940s/50s patterns are here (including pedal pushers, remember those?), and the 1950s/60s patterns here include a maternity top I remember my mother wearing, in apple green with white polka dots.