First off, $27,574 is $13.25 per hour, assuming the standard salary 40 hour weeks or $15.15 assuming hourly employee's standard 35 hour work week. This got me thinking: if kingreggieisreal got simple division wrong, what else did they get wrong...
Keeping in mind that conversion rate records from the time are lacking, from what we can surmise, in 1843 (when this story took place), a week's 15 shillings (£0.75) was worth about £110.90 today ($147.84 US). This would be about £5,766.8 per year ($7,688.76 US), or £2.77 per hour ($3.70 US) assuming 40-hour weeks, or £3.17 per hour ($4.22 US) assuming 35-hour weeks.
I'm not really sure what maths kingreggieisreal is using, but it seems flawed.