This article was written by Matt Castle, our brand-spanking-new writer who joins us from across the pond where U's are used liberally and R's and E's are juxtaposed brazenly.

One afternoon in the early 1950s, a young biochemist left his suburban lab bench at Britain’s Mill Hill National Institute of Medical Research and boarded a tube train to Leicester Square. His destination was on nearby Lisle Street, in an area which today makes up part of London’s glittering West End theatre district. But in the post-war years the sector was better known as a hectic hub for two of humanity’s oldest professions. Only one of these was of interest to the young scientist. The girls hawking their wares seemed to sense his single-mindedness and kept their distance as the greenhorn scientist turned his attention to his true quarry: the vast abundance of second-hand military hardware that could be found in the shops lining Lisle Street.

Specifically, he was looking for war surplus radar equipment. His intention was to cannibalize a suitable radio frequency transmitter for the purpose of reanimating dead, frozen hamsters.

The purposeful young biochemist was working in an exciting field so new that it didn’t yet have an official name, although eventually the term “cryobiology”⁠— literally meaning “frosty life”⁠— gained currency. One of his colleagues at Mill Hill was Dr Audrey Smith, the leading light in a series of hamster freezing and reanimation experiments. These dramatic and oft-quoted experiments have since achieved legendary status among cryobiologists, including researchers of the credible variety and researchers of the we’ll-freeze-your-head-and-bring-it- back-to-life-attached-to-the-body-of-a-spaniel-when-future-technology-allows variety. Yet they have never been repeated.

The basic procedure worked like this:

1. Obtain desired number of Golden Hamsters (Mesocricetus auratus).

2. Place in ice bath at temperature -5°C.

3. Leave hapless rodents to cool until hearts have stopped beating, respiration has ceased, animals are frozen rigid and are-– by any conventional definition of life⁠— no longer alive.

4. After 60-90 minutes, remove hamsters from ice bath.

5. If required, cut sections of one or more control animals to determine degree of freezing. Please note⁠— animals thus examined should not be used in subsequent reanimation attempts.

6. Warm the hearts of the frozen hamsters until they start up again, followed by gentle re-warming of the rest of the animal(s) until miraculous recovery occurs.

7. Determine number of survivors.

Serves 5.

In the initial experiments, reanimation of the hamsters was carried out using the crude method of pressing a hot metal spoon against the animal’s chest until circulation resumed. The important thing was to warm the heart first- the researchers soon found that simply placing the hamsters in a bath of warm water would lead to an over-rapid resumption of circulation, promptly stopping the heart again due to contact with the freezing cold blood returning from the animals’ extremities. By applying heat to the heart first a more gradual and ultimately successful reanimation could take place.

But it was felt that the use of the hot metal spoons was a step too far; the burning and singing of the skin caused obvious distress to the reanimated animals. The purpose of the young biochemist’s visit to Lisle Street was to make this aspect of the re-warming process more humane. By adapting an old aircraft radio frequency transmitter to emit microwaves, a diathermy device was made which could heat the hamsters’ hearts externally without damaging the skin in the same way a microwave oven cooks ready meals without melting the plastic container.

The astute scientist who pioneered this technique and later braved the whores of Lisle Street to find suitable equipment was a man named James Lovelock. In his autobiography Homage to Gaia he describes how his work on hamster-reanimation got him thinking about the meaning of life. According to conventional definitions of “life,” the frozen hamsters were decidedly dead; the unfortunate rodents weren’t moving, they weren’t breathing, their hearts had stopped, and they certainly weren’t eating, drinking or reproducing. Yet they could be made almost as good as new with a little bit of hot-spoon or microwave therapy. He wondered if “life” might have a broader meaning. This set him on the path to the theory for which he is most well known: the Gaia Hypothesis.

James Lovelock with statue of Gaia in background.  Photo (c) Comby Institute
James Lovelock with statue of Gaia in background. Photo (c) Comby Institute

Thirteen years after he left the Mill Hill laboratories and the field of cryobiology, he finally published the landmark paper Atmospheric homeostasis by and for the biosphere: the Gaia Hypothesis with his biologist collaborator, Lynn Margulis. Gaia theory proposes the existence of a system of complex feedback mechanisms that work across the whole of the Earth’s surface; these involve both living and non-living parts of the biosphere which act to keep the chemistry and temperature of the planetary surface comfortable for life. In some important respects this entire system could be considered as akin to ‘living’ itself. Lovelock’s novelist friend William Golding found an appropriate name from Greek mythology: that of the Earth Goddess, Gaia.

At first the idea was met with disbelief⁠— then with ridicule. To this day Gaia theory is still far from being universally accepted among the scientific community. Although Lovelock was careful to stress that his theory wasn’t suggesting that the Earth was actually alive⁠— only that the Earth system mimics a living, self-regulating entity in some ways⁠— many scientists struggled with the analogy. For a start the Earth doesn’t eat or move purposefully, and it has never displayed any discernible interest in mating with neighbouring planets. It was a difficult concept to reconcile with the traditionalist view that something was alive only if it met certain established criteria, such as being capable of metabolism or growth.

Meanwhile cryobiology research continued. By the time Lovelock left Mill Hill in the early 1960s the freezing and successful reanimation of hamsters using microwave diathermy was almost routine. But there were limitations to the technique. For a start, the temperatures involved never went further than a few degrees below the freezing point of water and only for an hour or so at a time; although in some cases more than 80% of the water in the skin and 60% of the water in the brain had changed to ice, the animals were never 100% frozen. Thus most of the hamsters’ cells were spared the tattering which is characteristic of full ice crystal formation.

The results were certainly dramatic, demonstrating that it is possible to lower complex organisms to below-freezing temperatures and then successfully reanimate them. The knowledge they gained had clear relevance to the aim of improving human health; current medical advances that derive from early cryobiology research include techniques for the storage and transport of human tissues destined for transplant, many aspects of low temperature surgery, and experimental techniques for improving outcomes in resuscitation after cardiac arrest. Though these researchers were not advocating the freezing of dead human bodies or heads for later reanimation, their research did become the basis for just such a movement⁠— a scandal-tainted offshoot of cryobiology known as cryonics.

A cryonics patient is prepared for freezing in a vat of dry ice.
A cryonics patient is prepared for freezing in a vat of dry ice.

But attempts to repeat the experiments with larger mammals and at lower temperatures have never been successful. And neither was the phenomenon entirely original: in the natural world numerous critters have been pulling a similar trick for millennia. Fish swim in freezing polar seas with antifreeze proteins in their blood, Wood Frogs’ circulation and breathing stops when they partially freeze during the winter, and even mammals like the Arctic Ground Squirrels can hibernate successfully at temperatures of -3°C, with no need to resort to microwave diathermy for reanimation after months, not minutes, spent at subzero temperatures.

Less spectacular but perhaps more significant experiments in cryobiology were also carried out by Smith’s team. Attempts to reanimate frozen sperm in 1949 were only successful when a mislabeled bottle of preservation solution was later found out to contain glycerol. Glycerol, which lowers the freezing point of water, is widely used to this day as a cryopreservative agent and has been found in many cold-loving creatures in nature. Dr Smith later investigated the phenomenon of supercooling, which involves techniques to prevent the formation of ice crystals in cells despite cooling them to temperatures below the freezing point of water.

Of course Mill Hill did not have a monopoly on ghoulish cryobiology experiments and related research was carried out elsewhere. Notably a researcher at Japan’s Kobe University, Isamu Suda, froze cat brains in solutions containing glycerol for extended periods in the 1960s. When the brains were re-warmed-– up to two and a half years later⁠— brainwave activity was recorded in some of the specimens. Suda, however, was unable ascertain whether frozen cat brains dream of electric mice.

These days ethical considerations limit the scope of such research. Animal experiments still take place at Mill Hill but only under a strict ethical review process which exhaustively balances any possible benefits of the research against actual or potential suffering to the animals involved. It can safely be assumed that the hamster freezing experiments in their original form would be well and truly off-menu.

The potential demonstrated by frozen-hamster research has yet to be fully realised, but perhaps one day Dr. Audrey Smith’s groundbreaking efforts will lay the foundation for powerful new medical procedures. Indeed, a hot over-sized spoon might one day miraculously transform frozen human cadavers back into living, breathing, productive zombies to slave away in the mechanized underworld of the future. Until that long-hoped-for day arrives, perhaps⁠— like James Lovelock⁠— we can console ourselves with the idea that this pioneering work has helped broaden the meaning of life.