Connecting rods – name and purpose

I see these iron rods connecting columns in outdated buildings everywhere in the historic world. Can anybody inform me what they’re known as and what precisely is their perform?

Listed below are examples from the Royal Fort at Lahore and St Marks Sq., Venice.

https://preview.redd.it/6o5eyjq5n6u91.jpg?width=800&format=pjpg&auto=webp&s=03202374d3d7cdff3ca18dc8829037f9f00e775f

https://preview.redd.it/me8r1oq5n6u91.jpg?width=947&format=pjpg&auto=webp&s=4c4856adfe21cb65acc5c623f1772c852114c3be