Review of the original U.S. edition:

In this book you will find instruction in subjects ranging from:

Glass Working

Gold Leafing

Gold Panning

Granny Squares

Greenhouse Construction

Greeting Cards

Hammocks and Slings

Hardanger Embroidery

Heraldry

Herbs

Hibachi and Hot-Pot Cookery

For British collectors looking for this edition to complete their set; I can confirm that it was never published in this form in the UK (Which only consisted of 19 volumes) although some of the contents did appear in other volumes.
It is likely that the reason for shortening the British edition by five books may be something to do with the printing budget (but we may never know for sure fourty years on).
It is probable that the cost of the total set had to be reduced in order to keep the total cost within a certain limit in order to appeal to more subscribers to the partworks in the UK. Although the filmsetting of the British reproduction was done in the UK, the printing and binding of the book were shipped out to a company in Holland.