If I read paragraph 5(b), it looks like the reading of paragraphs 5(a), (b), and (c), as originally intended, was that clocks and watches were one category. They're timepieces, in other words, whether they're portable or not.
Si je lis l'alinéa 5b), il semble à la lecture des alinéas 5a), b) et c), qu'au départ l'intention était que les horloges et les montres constituent une catégorie.