as an encyclopaedia set proudly lining your bookshelf – they’re barely worth the paper they’re printed on.
A big investment (around $800-$900 at the time), the set of some 32 books was once an essential part of homework time but the rise of CD encyclopaedias such as Encarta, and eventually the internet has killed any use the books once had.
“Modern, 20th-century encyclopaedias really aren’t worth anything at all now,” rare book dealer Derek McDonnell told ABC Radio Perth.
Second-hand bookshops can no longer sell them and some charity stores also reject them as they are no longer a desired item, not even for nostalgia's sake, McDonnell added.
Sold door to door, families could either purchase the books in one hit or become a subscriber to receive them in instalments. To own a set was quite an achievement.
"I'm 58 now and can still remember the door-to-door salesman selling my parents a set of Colliers Encyclopaedia in the late '60s," caller Jack told the show.
"They were great for settling arguments in the day ... they now rest at my place, I just couldn't bear to see them thrown out."