Britannia – apart from being a grandiose term for the United Kingdom, as in Britannia Rules the Waves – is a trade name for the line of machinery created in the 1870s by William Jackson, a young inventor. His rolling machines were the primary innovation that directly transformed every aspect of tea making in Assam. It shifted the global market in terms of production and consumption from China green to India black tea.

This is of more than just historical interest, because it addresses the very core of tea industry development over the last 150 years and for the foreseeable ones: (1) machines replace labor, (such as mass market bags and blends), (2) machines leverage labor, (mid-range whole leaf) (3) machines outperform labor (vacuum packaging and storage) (4) machines degrade labor (premium pedigree teas.)

Tea making has three main blocks of activity: Field, Factory and Distribution.


Mechanizing some of these stages greatly reduces quality and variety. This is especially so in plucking the leaf from the bush. The difference between the “two leaves and a bud” or Imperial plucking and machine shearing is equal to that of catching and preparing fresh, wild Pacific salmon and farm-raised frozen tilapia. This is machine versus labor. Equally, in packaging tea, warehouse storage and vacuum-packing of fresh leaf are completely superior to the handling of tea as if it were shovel loads of mulch. Here, machines outperform labor.

Rolling: sounds simple, definitely isn’t

Two aspects of Jackson’s innovations and the many related later ones stand out: first, what they didn’t automate and, second, the dramatic impacts that had on the processes that they did.

Jackson’s contribution was to dramatically improve the key middle rolling stage of black tea production: this follows the plucking and withering of the leaf. Rolling gets it to the right malleability, moisture and leaf structure for the oxidation step that activates the interaction of chemical compounds. These create its flavors, tea color and aroma.

Rolling is a simple sounding process that involves very complex timing and technique. It bruises the harvested leaf, once it has been withered to remove the moisture. This opens up the chloroplast cells in the green leaf, without damaging, deforming or fragmenting it. It releases the catalyst enzymes to start the chemical interactions (oxidation).

The scientific summary gives a hint of the molecular dynamics: “the polyphenoloxidase enzyme starts the oxidation of green catechins that form orange teaflavins. These then polymerize into brown thearubigins.” In lay terms this can be rephrased as “This is tricky and you have to get it right.” It requires plenty of pressure but gentle handling. The leaves must be kept rotating to shape them.

In China, green leaf is still hand rolled between a skilled worker’s palms, moving them anti-clockwise so that they form twists and curls. The Japanese technique that remains the equivalent of a specialty chef’s showcase performance moves the hands backwards and forwards to form neat round needles. For Assam’s black teas, the rolling was entire manual and followed by drying the tea over charcoal and then workers trampling it (with their feet) into wooden chests for shipping.  

Plenty of heat is produced during the rolling, especially in summer and autumn. It must be released at the right moments, to control the speed of oxidization of polyphenols. Jackson’s machines had to provide for varying the tea rotation with pressure and no pressure, maintaining the uniformity of the leaf structure while lightly breaking up its cells. The volumes were heavy: 100 kilograms became the standard batch unit, to be identified as an individual “lot” for auction. Later rollers handled 500 kg at a time.

Jackson’s innovations came at an opportune time. Assam’s teas could not compete with China’s because even the use of imported “coolie” labor could not match its low costs and higher experience. Productivity was very low, with rolling a disproportionate burden. Contemporaries constantly discuss the working into the nighttime to complete the work before the leaf lost its freshness, the tiny details that could wreck output, right down to too big a handful the worker picked up and how tightly he or she held it, and the size and ventilation of the room.

His machines were astonishingly complex, as is shown in the book extract below. There are fifteen pages at this level of detail. What stands out is both Jackson’s design ingenuity, engineering flair and also his knowledge of tea growing. (The source is Tea Factories and Tea Machinery, by Alexander James Wall, 1923. The book is a digitized, out of print Google reproduction; it was not exactly a best-seller in its time, but is very informative and surprisingly interesting.)

Extract from Tea Factories and Tea Machinery, by Alexander James Wall

All this was, of course, before electricity became widely available. Steam, wood and coal powered the engines. The climate was humid and corrosive – Assam was essentially a semi-primeval jungle. Spare parts could not be shipped in by FedEx.

Electrical power was demonstrated in India in 1879 and the first power supply was an 1890 hydroelectric plant near a Darjeeling tea estate. India’s first street lights were introduced in 1905 but it was only in 1923 that electrical power came to Assam.

The Scottish factor in English tea

Jackson was one of the great Scottish innovators who make the widely used term “English tea” misleading and asinine. Here’s an extract from a 1930s book (All About Tea, Vol. 2, 1935, William Harrison Ukers) that shows the anecdote of his accidentally discovering the opportunity that drove the industrialization of tea making in Assam.

Extract from the book All About Tea, Vol. 2, 1935, William Harrison Ukers

Jackson was British but not English, one of many Scots who should star in any Tea Hall of Fame:

Robert Fortune: Broke the Chinese stranglehold on tea growing through a strategy of anthropological field investigation and informal importation to Assam, a much nicer phrase than espionage and smuggling

The Bruce brothers: Discovered the Assamica variant of the tea bush. It took them many years to convince the tea authorities that this grew well and that Chinese implants didn’t.

James Taylor: Created and built the entire Ceylon tea industry, starting in 1867.

Lionel Davidson: An Assam tea farm manager, who invented just about everything Jackson hadn’t and whose patented Scirocco driers, rollers, packing machines, cutters and sorters  became as standard a name as Britannia. (Plus the propeller fan that revolutionized factory work conditions, mining and boats, belt rivets, munitions making machines in World War I and tennis poles.)

Thomas Lipton: Originally a grocer, then the creator of integrated tea production and retailing and originator of the most famous brand in its history. Had as profound an impact on everyday life as even Sam Walton.

All Scots, all self-made, all non aristocrats, and all supremely talented and tenacious. Oh; English Breakfast tea originated in Edinburgh, Scotland.

At the end of the 19th century, 8,000 of Jackson’s Britannia rolling and drying machines produced the output of 1.5 million workers. In 1872, Assam production cost was 11 pence a pound and completely uncompetitive with China’s exports. By 1912, it was less than 3 pence. The wood needed to convert to charcoal to dry a pound (lb) of tea dropped from 8 to 1/4. The daily rolling output of the average garden increased from 80 to 500 lbs. China exports of tea to the UK were 70 million lb in 1872 and 15 in 1912. Assam went from 0 to 219 million.

They also show how sharp the divergence of the Artisan and Agribusiness tea paths has been. The key difference rests on which stages of tea making are mechanized versus reliant on skilled labor. This has an immense impact on quality and cost and it really is worth knowing which one you’re considering or drink on a regular basis.

There were many reasons to focus on rolling. First, that was where much of the cost was. Second, the cost came from labor. Third, the process was manual and routine and did not rely on judgement and selectivity. That last point is absolutely central to the labor/machine trade-off, then and today.  

The Roller cometh…. The Rotovane is not far behind

That trade-off is captured by the next major generation of machines: the rotovane. This intervenes in the wither/roll/oxidate sequence. It is the base for the CTC method of producing black and, increasingly, green teas. In essence it’s a shredder. It substitutes turning the leaf into pellets rather than rolling the whole leaf.

CTC stands for Crush, Tear and Curl (sometimes Crush is replaced by Cut, but the result is the same). It was introduced in the 1930s and is now the mainstream for mass market teas. It is ideal for tea bags, using large leaf tea (predominant in Assam), thicker and lower grade ones (more and more the norm in large-scale lowland African, Bangladesh, Indonesian, Sri Lankan and Assam farms.)

This is sliced by blades, crushed and bruised, literally to get the juices flowing. It is then rolled by the rotovane to form very small grain pellets in uniform size. One commentary compares them to grapenut cereals, which are neither grapes nor nuts, but toasted breadcrumbs. This is tea toast.

The formation of the pellets starts the oxidation early and makes it faster. It produces a much darker and stronger brew in the cup. A whole leaf black tea takes 3-4 minutes to unfold its flavors in water at or just below boiling point. CTC tea bags need just half a minute and the strength of the pellets plus the larger surface area lets them permeate the typical food-grade plastic (don’t think too closely about what edible plastic actually means and don’t let the term potentially carcinogenic wander across your mind) or filter paper at lower temperatures.

CTC transformed the entire economics of tea. It turned it into a convenience. It is now over 80% of the market. It’s OK stuff, within its limits. Those limits are pretty tight. It’s fairly equivalent to tomatoes for salads. The supermarket tomato is grown year round, machine-picked, bred for durability and crop yield, refrigerated and artificially colored and ripened. It lacks the carotenoid sugars of vine-ripened varieties and comes from giant farms that make heavy use of pesticides.

Say that you had no idea that this tomato production system was not your only choice, that there were farmers’ markets with heirloom varieties like Cherokee Purple and Pink Brandywine, or that planting seeds deep in organic compost produces a deeper root system.

You didn’t know this? Welcome to the world of the teas of today. Most tea bag drinkers simply aren’t aware of the wider choices. The combination of CTC and the move towards machine harvesting – shear, snap and grab everything in reach, CTC and computerized process control throughout the factory gives you the equivalent of supermarket cotton tomato. The farmer’s market and organic produce section are its counterweight.

There will be more and more machines taking over from labor simply because there has to be; just as Jackson was key in enabling Assam to first survive and then thrive, the economics of the industry are inescapable. That will bring – is bringing – truly brutal social disruptions. The main labor force in Kenya faces massive job losses once the government ends its policy of no automation in the fields.

In Assam, the agribusiness farm communities face social chaos: the burning of a farm manager and his wife in their house because of months of unpaid wages, reported starvation and even several hundred suicides as farms fail, and workers lose their food subsidies. It’s part of an almost iron law of development: the machine drives out the people.

One the more positive side of the equation is that just as Jackson’s innovations helped make tea better quality at a lower price and for a more sustainable future, many developments have comparable payoffs. The supply chains of tea have been primitive for many hundreds of years, adding cost, delays, waste and spoilage. Vacuum packaging, intelligent machines with visualization and scanning capabilities for grading and sorting, automated storage management, and online integration from bush to cup are changing that. Clonal methods and DNA typing are creating a new generation of teas that are superior in all dimensions of quality and value.

Remember the farmer’s market when you shop for your tea. Be aware of the machine’s impact; in particular, don’t be fooled by fancy packaging into thinking that CTC and its variants of tea dust and fannings is the very lowest quality of what you can put in your pot and cup. You don’t have to stay with the supermarket offerings. Your choice. The Jackson tradition of machines to enhance labor still has a place, though the agribusiness ethos of automation is clearly sure to remain ascendant.

The banner features a roller still in use in Darjeeling. Photograph by Gautam Virprashad.