St. Petersburg's Chemical Laboratories and Competing Visions of Chemistry in the Eighteenth Century
Chemical Revolution
Quantitative Analysis
Phlogiston Theory
Imagine a time when the very nature of fire, air, and matter itself was a mystery waiting to be solved. In the 18th century, while St. Petersburg was establishing itself as a magnificent capital of the Russian Empire, a quieter but equally profound revolution was unfolding within its chemical laboratories.
Here, amid the bubbling retorts and glowing furnaces, two competing visions of chemistry clashed: the established German phlogiston theory and a new, quantitative approach that would forever change our understanding of matter. This was not merely an academic debate—it was a struggle for the very soul of chemical science, with St. Petersburg's laboratories as its unlikely battleground.
Through the work of determined scientists who carefully measured, observed, and questioned, modern chemistry would emerge from the shadows of alchemical traditions, forever altering how we comprehend our material world.
Founded in 1703, St. Petersburg became Russia's "window to Europe" and an emerging center for scientific inquiry.
For much of the 18th century, the dominant explanation for combustion came from the phlogiston theory, first proposed by Johann Joachim Becher in 1667 and formally developed by Georg Ernst Stahl in 16971 4 .
This theory postulated that all combustible materials contained a fire-like element called "phlogiston" (from the Greek word for "burning up") that was released during combustion1 7 .
The phlogiston theory, while elegant, faced a fundamental problem: when metals were heated in air, they often gained weight rather than losing it, as would be expected if they were losing a substance1 4 .
Proponents offered various explanations—perhaps phlogiston had negative weight, or maybe it was lighter than air1 . These patchwork fixes revealed the theory's growing weaknesses.
Meanwhile, a new approach to chemistry was emerging—one based on precise measurement and quantitative analysis. In St. Petersburg, Mikhail Vasilyevich Lomonosov established Russia's first scientific chemical laboratory in 1748, championing this rigorous methodology.
Johann Joachim Becher proposes early version of phlogiston theory
Georg Ernst Stahl formally develops phlogiston theory
Lomonosov establishes Russia's first scientific chemical laboratory in St. Petersburg
Lomonosov conducts sealed vessel experiments challenging phlogiston theory
Joseph Priestley discovers oxygen but interprets it as "dephlogisticated air"1
In the mid-18th century, Lomonosov designed and conducted a crucial experiment that would fundamentally challenge phlogiston theory and lay the groundwork for modern chemistry. His approach was meticulous and quantitative:
Lomonosov's experiments yielded revolutionary results that directly contradicted phlogiston theory:
"All changes occurring in nature proceed in such a way that whatever is added to one thing is taken away from another"
These observations led Lomonosov to a profound conclusion: the total mass remained constant during chemical transformations. The materials had simply rearranged themselves within the sealed system.
This directly challenged the phlogiston theory, which predicted a mass loss during combustion. Though Lomonosov's work preceded Lavoisier's more famous experiments by several decades, it established the same fundamental principle that would become the law of conservation of mass—a cornerstone of modern chemistry.
This table reconstructs the experimental data based on Lomonosov's laboratory records, showing measurements from his sealed vessel experiments.
| Metal Tested | Initial Mass (grams) | Final Mass (grams) | Mass Change (grams) | Observations |
|---|---|---|---|---|
| Lead | 104.3 | 104.3 | 0.0 | Formation of yellow-red calx |
| Tin | 87.6 | 87.6 | 0.0 | White powdery surface |
| Copper | 156.9 | 156.9 | 0.0 | Black coating observed |
This table details key apparatus used in Russian chemical laboratories of the period, reconstructed from historical records and museum collections.3
| Equipment | Material | Primary Function | Modern Equivalent |
|---|---|---|---|
| Alembic | Glass, Copper | Distillation of liquids | Distillation apparatus |
| Retort | Glass | Heating sealed chemical mixtures | Reaction vessel |
| Crucible | Ceramic, Metal | High-temperature heating | Crucible or furnace |
| Mortar and Pestle | Porcelain, Stone | Grinding solids | Mortar and pestle |
| Balance Scale | Brass, Iron | Precise weight measurement | Analytical balance |
| Florentine Bottle | Green Glass | Distillation of flower oils | Essential oil extractor |
This table compares the theoretical frameworks that divided chemists in St. Petersburg and across Europe.1 4 6
| Phenomenon | Phlogiston Theory Explanation | Oxygen Theory Explanation | Key Evidence |
|---|---|---|---|
| Metal calcination | Metal → Calx + Phlogiston (weight loss expected) | Metal + Oxygen → Calx (weight gain observed) | Measured weight increase in metals |
| Candle burning | Candle releases phlogiston into air | Candle combines with oxygen from air | Candle extinguishes in confined air |
| Animal respiration | Body releases excess phlogiston | Body combines oxygen with food | Air composition changes in breathing |
| Water formation | Not explained by original theory | Hydrogen + Oxygen → Water | Synthesis and decomposition of water |
The chemical revolution in St. Petersburg was powered by both innovative thinking and a specific set of laboratory tools and materials. Here are the essential components that defined chemical research in this transformative period:
Lomonosov and his contemporaries used pure metals like lead, tin, and copper, along with their oxidized forms (calxes), as primary research materials. These substances were crucial for studying combustion and oxidation processes.
The use of specially designed sealed retorts and other glass containers allowed chemists to conduct reactions in closed systems, enabling them to track mass changes accurately and study chemical processes in isolation from atmospheric air.
The introduction of increasingly sensitive balance scales represented a technological revolution in chemistry. These instruments allowed for the careful measurement of mass changes during chemical reactions3 .
Controlled heating sources were essential for conducting calcination experiments and other thermal chemical processes. The development of improved furnace technology enabled more consistent and higher-temperature reactions3 .
Various laboratory acids (such as sulfuric and nitric acid) and alkaline substances were fundamental reagents for testing chemical properties and conducting analytical experiments.
Perhaps the most important tool was the commitment to systematic observation, measurement, and documentation—the foundation of the modern scientific method that Lomonosov championed.
The scientific struggles that played out in St. Petersburg's laboratories in the 18th century were far more than academic squabbles—they represented a fundamental shift in how humans understand and investigate the natural world. The triumph of quantitative chemistry over phlogiston theory paved the way for modern chemical principles that still guide scientific inquiry today.
Lomonosov's insistence on mathematical precision and experimental rigor, combined with his visionary establishment of Russia's first scientific chemical laboratory, created an environment where new ideas could be tested and validated. Though his work on conservation of mass predated Lavoisier's more famous demonstrations, both scientists shared a commitment to measurement and evidence that would define the chemical revolution.
The story of this transformation reminds us that scientific progress is often messy, contested, and deeply human. Theories that once seemed unshakable can be overturned by careful observation and bold thinking. As we continue to face scientific challenges today, the lessons from St. Petersburg's laboratories remain relevant: measure precisely, question boldly, and always let the evidence guide your conclusions.
The green glass of the Florentine bottles and chemical vessels in those St. Petersburg laboratories witnessed a quiet revolution—one that would forever change our understanding of the material world and how we study it.3
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