Suitcases with wheels are killing the planet, or so one theory says. How? Well, wheeled suitcases tend to be bigger than the ones that have to be carried, so people put more in them, so not only are they bigger, they are heavier. Aircraft have to be bigger and heavier to carry the extra load, so they consume more fuel. The same goes for the cars that people use to get to the airport. More fuel equals more pollution, and more pollution equals more global warming. On that basis, the first person to strap a skateboard to a Samsonite has consigned the Earth to a terrible fate. And that, my friends, is the Law of Unintended Consequences in action.

Every email system is the same, right? Well, no, actually. Last week I decided to switch from BT Yahoo’s on-line email system to Google’s Gmail, to see what I thought of it for personal use. I know that some people have been using it for quite a while, and as such I’m not exactly an “early adopter”. However, these are my first impressions.

Prefect or praefect, in ancient Rome, various military and civil officers. Under the empire some prefects were very important. The Praetorian prefects (first appointed 2 B.C.) usually numbered two; they commanded the powerful Praetorians. From the 2nd cent. A.D. they had juridical functions, and important legists (e.g., Papinian and Ulpian) held the post. The prefect of the city was at first a deputy for absent consuls; the office fell out of use but was revived by Julius Caesar. Under the empire this prefect had power over the summary court for the region within 100 mi (160 km) of Rome. The prefect of the watch had charge of the fire brigade set up by Augustus. Augustus also established a prefect of the grain supply. There were other officers called prefects, such as the Roman viceroy of Egypt and many other officials of Italian cities.