SLOP8364 · Week 1

The birth of artificial cold

From the ice trade to Freon

Dr Simone Ravel

You own a machine that manufactures winter.

You pay a monthly bill for it.

You have never thought about it.

OpeningSLOP8364 · WK 1

Three questions, before I say anything

What is in your fridge right now that you will throw away?

When did you last smell something to decide whether to eat it?

What did your grandparents do in February that you do not do?

~6 min (0:03)

Hands up, then talk to the person beside you for three minutes. This is the first thing that happens in this course, and it is deliberate: the evidence base for the semester is their own kitchens, and I want that established in minute three rather than week four.

Take three or four answers out loud. Do not correct anybody. Write the answers on the board and leave them there for the whole two hours — I come back to them at the end.

Typical answers, in my experience:

Q1: half a bag of spinach, something in a takeaway container, condiments bought for one recipe. Almost nobody says “nothing.”
Q2: a lot of hesitation. Some say they never do. Some say they smell milk and nothing else. This is the competence question arriving early, and it arrives from them rather than from me, which is much better.
Q3: usually “preserving,” “gardening,” or a blank. The blank is the interesting answer.

Do not let this run past six minutes. It will want to.

FramingSLOP8364 · WK 1

What this course argues

The refrigerator is not a natural necessity.

It is a specific historical, technological and gendered construction — and it can be read the way you would read any other institution.

12weeks

1argument

4movements

FramingSLOP8364 · WK 1

The four movements

Weeks 1–3Disenchantment

Cold as a manufactured commodity. The myth sold alongside it.

Weeks 4–6Micropolitics

The interior as a jurisdiction. The door as a stage.

Weeks 7–9The tyranny of time

Date labels, waste, and the stuffed fridge as solace. Where it becomes measurable.

Weeks 10–12Resistance and reconstruction

Surveillance in the kitchen, degrowth, and what could be built instead.

FramingSLOP8364 · WK 1

What this course is not

Not a design course

We are not redesigning the fridge.

Not a sustainability course

“Waste less” is a conclusion, not a method.

Not about your moral failure

Nobody here throws food away because they are careless.

Part one

Coexisting with decay

For most of human history

People did not fight decay.

They coexisted with it.

Part one · Coexisting with decaySLOP8364 · WK 1

The techniques

Fermentation

Controlled microbial transformation

Drying

Removing the water that decay needs

Salting and curing

Osmotic pressure, applied patiently

Potting and confit

Sealing under fat

Cellaring

Cool and humid, not cold and dry

Each one is a different negotiation with time. None of them is refrigeration attempted badly.

Nobody invented cheese by trying to keep milk cold.

Part one · Coexisting with decaySLOP8364 · WK 1

What those techniques required

Knowledge

Which microbes, which salt, which temperature, how long.

Judgement

Is this ready, is this turning, is this gone.

A calendar

The work happened when the season said, not when you felt like it.

A household organised around all three

Skilled labour, largely women’s, almost entirely unwaged. Week 2 does the work.

~5 min (0:27)

This slide is the one the course is actually built on, so do not rush it.

Each of the four is a capacity, and capacities can be lost. That is the thread running to week 7: when the judgement in bullet two is outsourced to a number printed on a jar by a manufacturer’s legal department, something has been transferred, and it was not transferred to the household.

The fourth is the gendered one, and it is worth naming now even though week 2 does the work. That household organisation was labour, it was skilled, it was largely women’s, and it was almost entirely unwaged and unrecorded. When we say a technology “saved labour,” the first question is always: whose, and where did it go?

Ask: what happens to a skill when the thing that required it disappears? Expect “you lose it.” Push once: lose it how — individually, or across a generation? Nobody in this room chose to stop knowing this. It stopped being transmitted.

A skill nobody needs is not a skill anybody keeps.

The competence did not decline. Its transmission stopped.

Part one · Coexisting with decaySLOP8364 · WK 1

Decay as an actor, then decay as a loss

The old arrangement

Predictable

It followed the season.

Legible

You could see, smell and taste where you were in it.

Partly useful

Some of it you wanted.

The new arrangement

Deferred

Pushed out of sight, not removed.

Illegible

Hidden behind a closed opaque door.

Entirely a loss

There is no good version of it any more.

~6 min (0:33)

Two slides’ worth of material on one, so work it as a reveal: cover the right column, establish the old one on its own, then set them side by side out loud, pair by pair.

The word to dwell on is deferred. The fridge does not abolish decay. It buys time on it, and the debt is still owed. That is the thesis in mechanical form, and everything in week 8 is the invoice arriving.

“Illegible” is the sneaky one. A root cellar is open — you walk past it, you see the apples, the ones going soft are visible and you eat those first. A fridge is a closed opaque box in which the oldest item is at the back and by construction cannot be seen. Ask the room how many have found something unidentifiable at the back of theirs. Every hand goes up. That is not a personal failing, it is an architectural property of the object, and week 4 takes it apart properly.

Third pair: this is where the good version of decay disappears. In a fermenting household, some transformation is the product. In a refrigerating household, every transformation is a loss. We narrowed the range of acceptable outcomes to exactly one — unchanged — and then built a machine to enforce it.

Part two

Cold as a commodity

Part two · Cold as a commoditySLOP8364 · WK 1

The nineteenth century’s strangest business

Sell a substance that:

Falls from the sky

For free

And destroys itself in transit

Part two · Cold as a commodity

Frederic Tudor, the “Ice King”

1806Boston to Martinique,
in the brig Favorite

Cuts a pond, loads a brig, ships ice to the Caribbean. Loses a great deal of money.

Does it again. And again.

~4 min (0:42)

The detail worth having: the first voyage was the brig Favorite, roughly 130 tons of ice, February 1806. It was a commercial failure, and the failure was not melt — a surprising amount arrived.

The failure was that nobody in Martinique wanted ice. They had never had it. There was no ice-shaped hole in their lives, no icehouse to store it in, no bar that knew what to do with it.

This is the single most useful fact in the lecture, so make it explicit: Tudor’s real problem was not supply. It was demand, and demand had to be manufactured.

His method — and Rees is good on this — was to give it away first. Cold drinks free to bartenders until customers began asking for them, then charge, having created the taste. He also negotiated monopoly supply rights in the ports he entered.

Ask: what does it tell you about a need, that it had to be taught?

Part two · Cold as a commoditySLOP8364 · WK 1

Making the trade work

1825Wyeth’s horse-drawn ice cutter

Harvest stops being hand-sawn and becomes industrial.

SawdustInsulation, for free

A waste product of the timber mills, and the thing that made long voyages survivable.

1833Boston to Calcutta

The Tuscany sails. Roughly a third of the cargo melts. It is still a triumph.

~4 min (0:46)

Three innovations, none of them refrigeration.

Wyeth’s plough is the mechanisation of harvest — a grid scored into the pond, uniform blocks, horses instead of hands. Cost per ton collapses. Note that the technology arrived on the supply side long before anything cooled anything artificially.

Sawdust is my favourite detail, because it is an industrial by-product becoming the enabling condition for a different industry. Nothing about it was designed for ice.

Calcutta: the Tuscany, 1833, roughly 180 tons loaded and something like 100 tons landed. The British community there built an icehouse for it. New England pond water, sold at a profit, on the other side of the planet, in a sailing ship, before refrigeration existed. If a student ever tells you globalisation began with container shipping, this is the counter-example.

Part two · Cold as a commodity

Who paid for it

Ice cutting was seasonal, freezing, dangerous work.

Men and horses went through the ice. Ice houses collapsed.

The trade had routes, owners, insurers, futures, and a workforce — like any other extractive industry.

Part two · Cold as a commoditySLOP8364 · WK 1

And then it ended

Warm wintersPolluted pondsTyphoid traced to natural ice

And a competitor that did not depend on weather at all.

Break — ten minutes.

We resume at the hour.

Part three

Manufacture replaces harvest

Part three · Manufacture replaces harvestSLOP8364 · WK 1

Mechanical refrigeration comes first to industry

BreweriesMeatpackingCold storageShips

Decades before it comes to a kitchen.

The technology was not invented for the home. It was retrofitted to it.

~4 min (1:07)

The chronology matters and students consistently get it backwards. Vapour compression is a nineteenth-century industrial technology — Carré, Linde and others — and its first customers were businesses whose product spoiled at scale.

Two consequences worth stating:

First, refrigerated shipping restructured world agriculture before it restructured any household. Refrigerated meat over long distances meant Australia and Argentina could sell to Britain. Whole national economies reorganised around a cooling technology while domestic kitchens still had an insulated box and a delivery of pond ice.

Second — and this is the one to hold — the domestic fridge is an industrial machine that was shrunk and sold into a house. It arrives carrying industrial assumptions: continuous operation, standardised temperature, throughput. It was never designed around what a household actually does with food. Week 4 is essentially this observation, extended.

Part three · Manufacture replaces harvestSLOP8364 · WK 1

The problem with early refrigerants

Ammonia

Toxic

Sulfur dioxide

Asphyxiating

Methyl chloride

Flammable

Efficient. Well understood. And they leaked.

In a factory a leak is an industrial accident. In a kitchen it is a family.

Part three · Manufacture replaces harvest

1928Freon

Thomas Midgley Jr., working for General Motors and Frigidaire. Dichlorodifluoromethane, manufactured by a DuPont–GM joint venture.

Non-toxicNon-flammableStable

Demonstrated by inhaling a lungful and using it to blow out a candle.

[Midgley] had more impact on the atmosphere than any other single organism in Earth’s history.
J. R. McNeill, Something New Under the Sun (2000)

~4 min (1:19)

Midgley’s other major contribution was tetraethyl lead in petrol.

CFCs turned out to be so stable that they survive intact into the stratosphere, where UV breaks them up and the released chlorine catalyses ozone destruction. Molina and Rowland published that in 1974; the Montreal Protocol followed in 1987 and is, genuinely, the most successful environmental treaty we have.

The moral to avoid is “scientist bad.” Midgley was solving the exact problem he was asked to solve, and he solved it well. Nobody in 1928 had a framework in which “chemically inert” was a hazard.

The moral to actually draw: the property that made it safe indoors is the property that made it catastrophic outdoors. Stability at kitchen scale is persistence at planetary scale. A domestic virtue became an atmospheric vice without changing at all — only the boundary of the analysis moved.

That is a methodological instruction for this whole course. Where you draw the edge of the system determines what counts as a success.

Part three · Manufacture replaces harvestSLOP8364 · WK 1

What the compressor actually changed

Before

Harvested

Somewhere cold, when the weather allowed.

Shipped

At somebody’s cost and somebody’s risk.

Runs out

Finite, visible, diminishing in the box.

After

Manufactured

On site, by the machine in the room.

On demand

Continuous, invisible, metered.

Indefinitely

For as long as the bill is paid.

Cold stops being a delivery and becomes a utility.

A household’s relationship to decay

stopped being a skill

and became a subscription.

Part four

When every month is available

Part four · When every month is availableSLOP8364 · WK 1

What “season” used to mean

A constraint

On what could be eaten.

A calendar

For when work happened.

A shared condition

The whole community was in the same month.

Part four · When every month is availableSLOP8364 · WK 1

What it means now

A label. A marketing category. A preference. Strawberries in July, asparagus whenever — the constraint is gone.

FieldPackhouseTruckWarehouseSupermarketCarYour fridge

Six links are somebody’s business. The seventh is your kitchen, and you are its last-mile operator.

Part four · When every month is availableSLOP8364 · WK 1

Time became negotiable

If cold is purchasable, then time is purchasable.

Buy in bulkCook on Sunday for ThursdayKeep the option open

Every one of those is a small, sensible, individually rational decision.

~4 min (1:36)

Be genuinely even-handed here, because the argument is stronger for it and because the room will stop trusting a lecture that only prosecutes.

These are real gains. Bulk buying is cheaper and matters most to the people with the least money. Batch cooking buys time back for people working multiple jobs. Leftovers kept safely are food not wasted. A fridge is a significant public health technology — safe milk, safe meat, safe insulin. None of that is in dispute and I want it on the record in week 1.

The claim is not that the fridge is bad. It is that the fridge sells a particular thing — deferral — and that the price of deferral is not visible at the point of sale.

Then the setup for week 9: what does “keep the option open” cost, if the option is never exercised? Hold that question. It is the whole back half of the course.

Part five

Political economy, at the scale of one box

Part five · Political economySLOP8364 · WK 1

What we mean by political economy

Not economics. Not politics.

The study of who gets what, and of the arrangements of power and property that decide it.

Usual unit of analysisStatesIndustriesClassesOne appliance, in one kitchen

~4 min (1:41)

Define the term properly once, now, because it is in the course title and they will use it for twelve weeks.

The unusual move is the scale. Political economy at the scale of a nation is ordinary. At the scale of a household appliance it sounds like a category error, and part of the intellectual work of this course is showing that it is not.

Why it is not: the fridge is where a very large number of systems terminate in a small number of decisions. Agricultural policy, energy generation, retail concentration, food safety regulation, advertising, gendered domestic labour, municipal waste — all of it converges on one person at 11pm deciding whether the leftovers are still all right.

The fridge is where a global system becomes a personal decision. That is why it is worth a semester, and it is the best answer to give when somebody at a party asks what the course is about.

Part five · The methodSLOP8364 · WK 1

Reading one object

For anything in a kitchen, ask:

Who built it, and what were they selling?

What capacity did it replace, and where did that go?

What does it make visible? What does it hide?

Who pays when it fails — and in what currency?

~5 min (1:45)

This is the course’s method on one slide. Tell them to photograph it.

Run the fridge through all four out loud so they see the machine work:

GM, DuPont, Frigidaire, Kelvinator — selling appliances, and from week 2, selling modernity itself with the appliance attached.
Preservation skill, seasonal knowledge, sensory judgement. It went nowhere. It stopped being transmitted, which is not the same as being destroyed and is harder to reverse.
Visible: the front of the shelf, the door, the performance of a stocked household (week 6). Hidden: the back of the shelf, the energy draw, the supply chain, the eventual bin.
The household pays, in money, in wasted food, in the unpaid labour of managing the box — and the planet pays in emissions and methane. Not the manufacturer, and not the retailer whose bulk pricing encouraged the over-purchase.

Then invite them to run it on something else — a freezer, a microwave, a supermarket loyalty card, a meal-kit subscription. Take one from the floor and do it live. It works on all of them, and watching it work on an object they chose is what convinces people the method is real.

The fridge sells you time,

and the bill arrives as waste.

Part five · FalsificationSLOP8364 · WK 1

What would prove me wrong

Households with fridges waste less food than comparable households without, controlling for income

Week 8 measures

The lost competence turns out not to be lost — people can still judge food without a label

Week 7 tests

The time bought is actually used, rather than banked and forgotten

Week 9 asks

A thesis that cannot fail is not a thesis. All three tests are already in the syllabus.

Back to the board

What is in your fridge right now that you will throw away?

You answered that in minute three, before any of this.

You already had the evidence. You just did not have the argument.

Wednesday · Session 01SLOP8364 · WK 1

Three samples of the same vegetable. Unlabelled.

APicked fresh

BRefrigerated three days

CFreeze-dried and rehydrated

You taste all three without knowing which is which, and write a description of each before the reveal.

~4 min (2:02)

Non-negotiable logistics, so say all of it:

Do not skip this one. It cannot be repeated once you know what the samples are, and it is one of only two exercises in the course that cannot be made up later.
Email me by Monday about any allergy or dietary requirement. The samples get adjusted; nobody sits out the first tutorial.
Read the Rees excerpts first. Nothing else to prepare — materials are supplied, and they have to be, because the whole thing depends on you not knowing.
Describe, do not guess. Texture, moisture, smell, colour, taste, in your own words. The instinct is to try to identify which is which. Resist it; that is not the exercise and it wrecks the data.
Keep your three descriptions. They are your own baseline and people use them in the Critical Essay every year.

What reliably happens, though do not tell them in advance: the room agrees strongly about texture and disagrees completely about which sample is “freshest,” and several people find they preferred one they would have rejected if it had carried a label.

Is “freshness” a physical state,

or a claim made about food?

Before WednesdaySLOP8364 · WK 1

Before Wednesday

Read

Jonathan Rees, Refrigeration Nation: A History of Ice, Appliances, and Enterprise in America (2013), excerpts.

Email me

If you have an allergy or dietary requirement.

Bring

Nothing. Everything is supplied.

Next week · Week 2

The totem of modernity

Advertising, gender, and the second shift. Technology promised to liberate the housewife. It raised the standard instead.

The birth of artificial cold

You own a machine that manufactures winter.

You pay a monthly bill for it.

You have never thought about it.

Three questions, before I say anything#

What this course argues#

The four movements#

What this course is not#

Coexisting with decay#

People did not fight decay.

They coexisted with it.

The techniques#

Nobody invented cheese by trying to keep milk cold.

What those techniques required#

Decay as an actor, then decay as a loss#

Cold as a commodity#

The nineteenth century’s strangest business#

Frederic Tudor, the “Ice King”

Making the trade work#

Who paid for it

And then it ended#

Break — ten minutes.#

Manufacture replaces harvest#

Mechanical refrigeration comes first to industry#

The problem with early refrigerants#

What the compressor actually changed#

A household’s relationship to decay

stopped being a skill

and became a subscription.

When every month is available#

What “season” used to mean#

What it means now#

Time became negotiable#

Political economy, at the scale of one box#

What we mean by political economy#

Reading one object#

What would prove me wrong#

What is in your fridge right now that you will throw away?

Wednesday: the blind tasting#

Is “freshness” a physical state,

or a claim made about food?

Before Wednesday#

The totem of modernity#

Three questions, before I say anything

What this course argues

The four movements

What this course is not

Coexisting with decay

The techniques

What those techniques required

Decay as an actor, then decay as a loss

Cold as a commodity

The nineteenth century’s strangest business

Making the trade work

And then it ended

Break — ten minutes.

Manufacture replaces harvest

Mechanical refrigeration comes first to industry

The problem with early refrigerants

What the compressor actually changed

When every month is available

What “season” used to mean

What it means now

Time became negotiable

Political economy, at the scale of one box

What we mean by political economy

Reading one object

What would prove me wrong

Wednesday: the blind tasting

Before Wednesday

The totem of modernity