20th Century Inventions: a Forecast, by Sutherland, 1901.
So here's what you should be looking for:
- Efficient capture of wind and wave power to make electricity. Sun, not so much, that's too hard.
- Electrical power used more in mining, factories, and farms to reduce human and horse labor.
- Cars to drive you to the railway station. Or maybe duel-purpose vehicles that can go on roads or rail, and link up to form trains. Could take you right to your door.
- Torpedoes! Maybe could even guide them by wire. Not submarines, those are stupid. Maybe colony attack ships -- one ship made of many little ones. Would be hard to stop.
- Artificial fertilizers for plants.
- Telephones that ring when someone calls you. Alarm clocks. Smart-homes -- or at least systems controlled by timers.
- Fans in your home for ventilation. But first we need some genius like maybe that Hungarian Tesla guy to come up with a way to make AC work for more than just lighting.
- Texting. Well, better automation in sending Morse code and better results in wireless telegraphy.
- Metronomes. Pianos that can hold notes. Electronic devices that help you practice your scales silently because apparently that really annoys Sutherland.
- Fax machine.