Money down the pan

12th May 2006 at 01:00
Q: One of my pupils asked me where the expression "to spend a penny" for going to the lavatory originated. I am sure there must be some maths in there somewhere.

A: Masses of maths can be gleaned from this euphemism. A cross-curricular approach with history could be interesting and lead to a look at current earnings and legislation on the number of hours an employer can ask you to work (48 hours a week unless a waiver is signed).

There was a time when public toilets had a coin box and you had to pay to use them. At large stations today you pay 20p for entry but there are no coin slots on the cubical doors.

J G Jenkins made public lavatories popular by installing them at the Great Exhibition of 1851 held in the Crystal Palace in Hyde Park, London. To use these toilets you had to pay an old penny (1d, approximately 0.417p). But you had already had to pay five shillings to enter the exhibition (5s, 1s = 12d). This price later dropped to one shilling. The exhibition was opened on May 1 by Queen Victoria. More than six million visitors attended between then and October when the exhibition closed. Various internet sites suggest that 827,000 people paid to use the toilets. You can already see the maths evolving. As a child I can remember having to pay to use public toilets - fine if you had the cash. Your question made me wonder about the relative cost of using public toilets in the past. Was "paying a penny"

comparatively expensive in 1851? What would the equivalent be today? Pupils could be given relevant facts and figures and asked to answer these questions.

A straightforward conversion between old money and new wouldn't really provide a meaningful comparison. A better one would be to find how long it took a Victorian worker to earn 1d and compare it with the time it took someone today. To do this we also need to remember that although the pound sterling remains the same, the number of pennies in the pound changed during decimalisation. Pre-decimalisation there were 240 pennies in pound;1. In a decimal pound;1 there are 100. As a ratio we can see that 240d is equivalent to 100p or, in simpler terms, 2.4d is equivalent to 1p. I can remember that a six-penny piece (6d) was worth 2.5p, 6 V 2.4 = 2.5.

An internet search provided some interesting figures. An average working week in 1851 was 14 hours a day, seven days a week. Some employers observed Sunday as the Sabbath; I have used a six-day week. The various sources on the internet do not state what kind of average is quoted so the average working week is taken as 84 hours.

When I looked up average earnings I could find them only for 1865. I asked the Union of Construction, Allied Trades and Tradesmen for up-to-date comparative earnings.

For the 1865 84-hour week, a labourer would take about 1 hour 52 minutes (84 V45) and the carpenter about 1 hour 4 minutes (84 V 78) to earn one old penny.

The hourly rate of the modern equivalent of a town labourer, a general operative, is pound;6.77. In 1 hour and 52 minutes the general operative earns pound;12.64. So "to spend a penny" would cost a general operative Pounds 12.64. A carpenter, whose hourly rate is pound;9, would have to work for just over the hour, and earn pound;9.60. I suppose to make it fair we would have to round the cost to pound;10. So the modern-day equivalent would be "to spend a tenner". Not quite the same ring.

Makes the pound;1 in Harrods' luxury cloakroom sound quite inexpensive!

* Facts and figures on working hours

www.manchester2002-uk.comhistoryvictorianVictorian1.html customsquestionscost.html has a table of the cost-of-living from the Victorian times and today.


Weekly wage for 84-hour week

Town labourer ( 2006 a general operative)

3s 9d (45d, 12d = 1s, 3 x 12 + 9 = 45, which is about 19p)


Weekly take home pay for 39-hour week


Carpenter (2006 craft rate


Weekly wage for 84-hour week

6s 6d (78d, 6 x 12 + 6 78, which is about 33p)


Weekly take home pay for 39-hour week


* Wendy Fortescue-Hubbard is a teacher and game inventor. She has been awarded a three-year fellowship by the National Endowment for Science, Technology and the Arts (NESTA) to spread maths to the masses.

*Email your questions to Mathagony Aunt at Or write to TES Teacher, Admiral House, 66-68 East Smithfield, London E1W 1BX

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