Edinburgh Rock: Sweetie Sandy's Crumbly Sticks

Each major claim carries one of three labels. established means supported by primary records, official bodies or several independent reliable sources. shared means the core fact is sound but sources disagree on details, dates or interpretation. traditional means widely repeated but not traceable to a primary or independent source.

Ferguson's role is widely accepted, though early documentation is limited. The accidental discovery story is legend. The fullest older account is by the folklorist F. Marian McNeill in The Scots Kitchen (1929; second edition 1963). She was writing while the firm still traded and records what was then known of its founder; her biographical details are useful but were not drawn from cited documents, and she presents the discovery story with "is said to". Alan Davidson's The Oxford Companion to Food (3rd edn, ed. Tom Jaine, 2014) is used for the confectionery science and for comparison with other rock. Its entry on rock is unsigned and cites Laura Mason's essay on the history of rock (1995); its entry on sugar boiling is signed by Mason. Neither mentions Ferguson.

What is Edinburgh rock?

established Edinburgh rock is made by boiling sugar, water and cream of tartar, then pouring the mixture out, adding colour and flavour, and pulling it until it becomes opaque. It is cut into sticks and left in a warm, dry place, where the sugar crystallises and the sticks become soft and crumbly. The result is quite unlike seaside rock, which is hard and brittle.

established McNeill's recipe shows the method plainly. Crushed loaf sugar and water are boiled with a pinch of cream of tartar to about 250–260°F (the hard-ball stage, higher in hot weather), poured on a buttered marble slab, the edges turned in as it cools, then dusted with sugar and pulled gently, "being careful not to twist it", until dull. It is snipped into pieces with scissors and left in a warm room for at least twenty-four hours "until the process of granulation is complete". The pulling and the long rest are what make it powdery rather than glassy.

The science of the crumble

established The Oxford Companion to Food (3rd edn, 2014) explains why. Its entry on rock says Edinburgh rock is made from a conventional sugar syrup "in which little attempt is made to inhibit crystallization", so that pulling forms a mass of very small crystals. The sticks are then left exposed to the air for a day, absorb moisture and become crumbly. Laura Mason's entry on sugar boiling makes the same point from the chemistry side: a syrup boiled to the hard-ball stage (121–130 °C), pulled and left to mature uncovered starts to recrystallise, and Edinburgh rock exploits this to get its friable texture.

established This is the opposite of what a maker of seaside rock or boiled sweets wants. Mason explains that cream of tartar and other acids help sucrose break down into simpler sugars, which interferes with crystallisation and keeps boiled sugar clear and glassy. Modern makers add glucose for the same reason. McNeill's recipe uses only a pinch of cream of tartar, too little to stop the rock graining once it has been pulled and rested. The pulling and the exposed rest do the work.

established Seaside rock is boiled hotter, to the soft-crack stage (132–143 °C), and kept from crystallising. It is a plain pulled candy, always made professionally because the pulling is complex. Its lettering is built at a large size from coloured hot sugar inside a white core and a coloured skin, and the whole assembly is drawn out until thin, so that the letters run the length of the stick.

Colours and flavours

shared Modern Edinburgh rock is sold in a range of pastel colours, and the flavour-to-colour match varies by maker. McNeill gives a fixed scheme: white for lemon or vanilla, pink for raspberry or rose, fawn for ginger and yellow for orange or tangerine. The Oxford Companion to Food gives nearly the same scheme: white with vanilla, lemon or mint; pink with raspberry or rose water; yellow with orange; and beige with ginger. Mint therefore has some standing as a white flavour, but green sticks appear in neither source and are probably a later addition or one maker's practice.

The original rock?

shared The Companion makes a bold claim: of the two British kinds of rock, Edinburgh rock "is the original form of the sweet", though it remains mainly a local speciality. Its reasoning is that pulled sugar and pulled candy go back to the Middle Ages, while rock with letters running through it is probably a recent invention. The first person to remark on lettered rock was Henry Mayhew in the 1860s, who noted in his survey of London's street trades that a sweet vendor had recently put short sentences into sugar sticks, such as "Do you love me" and "Sir Robert Peel". The Companion does not explain what earlier Edinburgh rock it has in mind, and Ferguson's own start is dated only to the 1820s. The claim is best read as saying that the crumbly, unlettered stick is the older style of rock, not that Edinburgh rock as now made predates all others.

Sweetie Sandy

established Alexander Ferguson, born in Doune, Perthshire, learned confectionery and set up in business in Edinburgh, traditionally in 1822. His sweets, including Edinburgh rock, were popular, and he was known as "Sweetie Sandy". The business continued after his death.

shared McNeill adds a fuller portrait, which should be read as family and local tradition. She gives his birth year as 1798 and says that as a boy he boiled sweet-smelling mixtures in old tins in his father's outhouses, to the scorn of his father, a joiner. He learned the trade with a Glasgow confectioner before setting up on his own in Edinburgh and prospering "thanks mainly to one speciality". He retired to Doune with a fortune, enlarged the family home, collected a library and laid out a garden. He was remembered there as a white-bearded old man in a black velvet jacket and white trousers who handed sweets to children from his pockets. McNeill quotes a comic verse by John W. Oliver about crowds flocking to Melbourne Place, "It's Ferguson who's boiling up / His Edinburgh rock."

The forgotten batch

traditional According to a popular story, Ferguson discovered Edinburgh rock by accident when a batch of boiled sweets was left forgotten for some months and crystallised, becoming soft and crumbly. The story is told widely, but there is no contemporary evidence. McNeill gives it in 1929 with the hedge that the rock "is said to have been 'discovered' more or less accidentally", after a set-aside batch was found months later transformed. The story is at least plausible in kind, since the long granulation rest is the essential step of the recipe, but there is no record of the event.

A souvenir

established Edinburgh rock became a popular souvenir for visitors to the city, sold in tins and boxes decorated with images of Edinburgh Castle. It is still made and sold today. In 1963 McNeill describes it packed in tartan boxes, mainly Ferguson and Royal Stewart, finding its way "to every corner of the Commonwealth". She also notes that confectionery was then an important Edinburgh industry and rock "one of the triumphs of the Scottish confectioner's art".

A wider sweetie tradition

established McNeill sets Edinburgh rock among Scotland's many local sweets: Jeddart snails, Berwick cockles, Galashiels soor plooms, Brechin's starrie rock, Moffat whirlies and others. She explains the national sweet tooth by the West of Scotland sugar-refining industry, which grew from about 1680 when sugar began arriving in bulk from the West Indies.

established The Oxford Companion to Food's entry on sweeties, which draws on Jenny Carter and Janet Rae, adds that the first manufacturing confectioner in Edinburgh was an Italian licensed in 1665 to make "confeits", and that Glasgow's confectioners multiplied once it became a sugar-refining centre. It ends its list of Scottish sweeties by sending the reader to rock for Edinburgh's contribution.

• Edinburgh rock is soft and crumbly, not hard.
• It comes in pastel colours.
• Alexander Ferguson was known as "Sweetie Sandy".
• Ferguson came from Doune, in Perthshire.
• The accidental discovery story is a legend.
• Edinburgh rock is left in a warm room for at least a day to turn powdery.
• It is pulled, but not twisted, and cut with scissors.
• Sweetie Sandy retired rich to Doune and handed out sweets to local children.
• Seaside rock with words running through it is first recorded in London in the 1860s.
• Edinburgh rock is boiled cooler than seaside rock, to the hard-ball rather than the soft-crack stage.

• Disputed: Ferguson discovered the rock when a forgotten batch crystallised. McNeill gave the story in 1929 with the hedge that the rock "is said to have been 'discovered' more or less accidentally". It fits the recipe's long rest, but there is no record of the event.
• Myth: Cream of tartar makes Edinburgh rock crumbly. Cream of tartar works against crystallisation, and McNeill's recipe uses only a pinch. The crumbly texture comes from pulling the syrup and resting the sticks exposed to the air.
• Disputed: Edinburgh rock is the original rock. The Oxford Companion to Food says so, reasoning that lettered rock is a recent invention. It offers no early evidence for the Edinburgh sweet itself, and Ferguson's own start is dated only to the 1820s.
• Disputed: the traditional colours. McNeill gives white, pink, fawn and yellow. The Companion gives nearly the same scheme but adds mint to the white sticks. Green appears in neither, so green sticks are probably a later addition or one maker's practice.