Fragile things, books. They can crease and tear at the slightest touch. Life, too, if you think about it. When his five-month-old son Josh was rushed to a Swiss hospital with a growth on his chest the size of a man's fist, everything suddenly seemed vulnerable in Simon Rosenheim's world. The 38-year-old publisher and his wife had to stand by and watch as Josh was cut open and the hole in his chest doused in the medical equivalent of Domestos.

Josh was suffering from osteomyelitis, a bone infection. ''He didn't have a breastbone,'' his father explains. ''There was nothing left. It had been eaten away.'' Josh stayed in hospital for a month, in a ward full of children who were suffering even more distressing - even terminal - illnesses. The experience planted a seed in Rosenheim's mind. As he explains: ''I felt if I was ever in the position to give something back then I wanted to be able to.''

His chance came seven years later. Inspired by the gift of a hard-wearing motorcycle map and a visit to the local doctor's surgery, where all the children's books in the waiting area were mangled and torn, he came up with the idea of tear-proof children's books. Books For Life, as he calls them.

''People have had the idea before,'' he admits, ''but haven't been able to do it economically.'' Rosenheim worked with a paper mill in Asia, to develop the paper, and the first books were published last May. Not only are they impressively hard-wearing, they're waterproof and also infection resistant, and so can even be used in intensive care units.

Josh is eight now and the only memento of his traumatic early days is a nasty scar on his chest. His favourite Book For Life is Big Mum Plum! As for his father, he's beginning to fulfil the vow he made when Josh was in hospital in Berne. Already four hospitals have benefited from donations of Books For Life titles and hospitals in Dundee, Glasgow and Edinburgh will hopefully be among the next recipients. Rosenheim already knows just how gratefully they are received.

''We were in Great Ormond Street a couple of weeks ago. There was this wonderful girl who has leukemia, and the utter squealing delight on her face when she was running our books underwater just brought it all back home. I just sat and watched quietly as she read one of our books to her parents who sat their with tears running down their cheeks. You cannot fail to be moved.'' n

Six new Books For Life titles are published this month by Meadowside Books, priced (pounds) 4.99 each.