So, this is how the research process goes: Look up the London Foundling Hospital; come across Hogarth being himself 'lampooned' for his humane horror at the indiscriminate slaughter of dogs on the streets during a spate of Rabies cases (reward offered for each dog carcass, regards of whether or not that animal had exhibited symptoms ); Aristotle on Rabies ( sometimes caused in dogs by contact with menstrual blood apparently!); Madrid in 1763, 900 dogs killed in one day and the early mention of Rabies in Britain in the Laws of Hywel Dda. A healthy scepticism regarding sources is, of course, desirable.
As my Mum describes me 'fel ci mewn coed' - chasing off after every scent! Can't use most of it, (haven't managed to get the Aristotole in, sadly) but I have now got a scene where the disease, called Hydrophobia in the Eighteenth Century, is part of the plot. Writing seems to be a heady mixture of planning, for instance I had the end of The Dipping Pool written seven years ago; research including open-minded 'laissez-faire', a 'see where it leads' approach; memory; the surfacing of subconscious obsessions and sheer hard graft of putting the puzzle together and editing it.
I love just going 'off piste' sometimes - finding myself writing a section that pops up as I'm in the manuscript file. I can't always use it, but being open to a random idea is most of the fun and occasionally something really interesting surfaces that you could have spent a lifetime planning and not found consciously. The same with research. You go looking for facts to make the scenario as vivid as possible but get taken in all different directions along the way. Going with it takes time, but keeps you interested and again you can find unexpected gems that take the work in a whole different direction.