A few weeks ago I came across this in a charity shop.
It’s from a huge and diverse series called Lets Read and Find Out published by A&C Black. Titles ranged from Watch Honey Bees with Me to The Sun: Our Nearest Star.
I spent many years editing Scholastic Children’s Books’ Horrible Science series and I love a bit of illustrated non fiction.
Don Madden’s illustrations are an absolute joy – I gather he illustrated many, if not all, of the titles in this series. I particularly love the cat and dog onlookers/assistants. I hadn’t come across him before, but I shall certainly be looking for more.
Gravity on different planets
Through the Earth
Three Wishes Books 
what a fantastic book!