‘We’ll put that aside for the moment. I’m thinking of a case where what we’ll call anæmia of the brain was masked (I don’t say cured) by vibration. He couldn’t sleep, or thought he couldn’t, but a steamer voyage and the thump of the screw——’
‘A steamer? After what I’ve told you!’ Conroy almost shrieked. ‘I’d sooner . . . ’
‘Of course not a steamer in your case, but a long railway journey the next time you think it will trouble you. It sounds absurd, but——’
‘I’d try anything. I nearly have,’ Conroy sighed.
‘Nonsense! I’ve given you a tonic that will clear that notion from your head. Give the train a chance, and don’t begin the journey by bucking yourself up with tabloids. Take them along, but hold them in reserve—in reserve.’
This is from "In the Same Boat " by Rudyard Kipling.
https://www.kiplingsociety.co.uk/tale/in-the-same-boat.htm
I don't understand the meaning below---
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--begin the journey by bucking yourself up with tabloids.
What are the tabloids?
I am glad if someone would kindly teach me.