The mystery of the stormglass - home weather station on the element base of the early XIX century
Articles about the manufacture and use of home weather stations are published regularly on Hiktames. I decided to keep up with the trend and also write a story about a weather station that hangs outside my window - about a stormglass.
In short, the stormglass is a flask with camphor solution used to observe the weather in the 19th century. There is a lot of information about him in the network - but the descriptions of the principle of operation usually boil down to the esoteric “I have not received a full scientific explanation.” A few years ago I read about the stormglass, became interested, made myself like this, experimented at home for several days, then hung the flask by the window and for the second year I observed its behavior in real conditions.
Such stormglasses sell on ebay - the crystals look beautiful, but by their appearance I can say that the stormglass was used idly, and the weather now does not show.
The explanation of the principle of operation turned out to be incredibly simple, and the device itself was sensitive enough so that I could, looking at it, understand how to dress when leaving home.
Stormglass is known largely due to Captain Fitzroy , the very one who drove Darwin on a world tour. In a nutshell, the stormglass is a solution of camphor in diluted alcohol, with the addition of inorganic salts. The solution is unstable, and when the weather conditions change, camphor crystals fall out of it, the number and form of which can be used to judge the weather.
I did not find any clear explanations of the principle of the stormglass operation on the Internet, but, in general, it was clear that the main "factors" of the weather are temperature, pressure, humidity, insolation, and, perhaps, something like an electromagnetic field. It is known that in old meteorological stations, stormglasses usually were sealed flasks, which means they could not measure pressure and humidity. In the visible part of the spectrum, the stormglass solution is transparent, and the ultraviolet glass flask does not let through well, so the reaction to sunlight is also unlikely. Eliminating the effect of electromagnetic fields on a solution or factors unknown to science was more difficult - but it still seemed to me most likely that the storm glass responds to temperature fluctuations.
My stormglass shows that it is cool and gradually getting colder.
I thought about all this before making my bottle. The first experiments showed me right. The fact is that the solubility of camphor in a mixture of alcohol and water strongly depends on temperature: it is enough to warm the solution slightly, and it becomes transparent, it is enough to cool it - and the whole flask will be filled with white camphor flakes. At the same time, the principle by which the composition of the solution was chosen was made clear: the ratio of the amounts of alcohol and water was taken so that in warm weather most of the camphor would dissolve, and in the cold it would precipitate; then, as the temperature changes, the amount of camphor flakes will change most noticeably. Mineral salts are needed in order to increase the density of the solution; due to the addition of these salts, the density of the solution is about the same
These were common words. Now a few observations:
In the comments, the question arose: "How is the size of the crystals related to the rate of temperature change?"
Of course, to fully predict the weather, just observing the temperature dynamics is not enough - in fact, even modern meteorologists, who have the most powerful computers and a network of meteorological stations that enveloped the entire planet, are not very good at this task. But in the conditions of the beginning of the XIX century, when even the most banal thermograph seemed to be a high-tech device - and in sea conditions, when the thermograph had to somehow be protected from ship rolling, the stormglass functions were in demand.
Now a little about making a stormglass:
I took the recipe from Wikipedia as a basis:
Potassium nitrate and ammonia are potassium nitrate and ammonium chloride, respectively, you can buy them at the hardware store. 10% camphor solution is sold in a pharmacy.
The concentration of camphor is not very important - I read about stormglasses made directly from the pharmacy 10% solution. But, if you (like me) do not want to move too far from the recipe, add water to camphor's solution - camphor will immediately precipitate in the form of large dense flakes that are easy to filter (for example, with a nonwoven napkin), dry (note that Camphor evaporates during drying, and it should be taken with a margin) and dissolved in alcohol again, to the desired concentration.
If the salts you took in the hardware store, they are most likely dirty and should be recrystallized. This is also simple: take boiling water (better distilled from the auto parts store), pour so much salt into it so that it stops dissolving, defend the solution (or better filter it through the same non-woven napkin), cool it to room temperature, collect the fallen out bottom sediment salts and also dry it.
Now you mix the components in the right proportion, and get a semi-working stormglass.
Another stormglass with beautiful crystals. If your will stand in the room, and not hang outside the window, then something similar may grow in it.
“Conventionally” - because it also needs to be calibrated for your weather. This is a bit boring, but also easy: take the resulting mixture, slowly heat it to the temperature that you want to make the maximum operating temperature - for example, the temperature hanging outside your window shows on a moderately hot summer day. Now make sure that very little camphor remains at the bottom of the tank with the mixture: if camphor has dissolved all, with constant stirring, add water to the solution drop by drop until a little sediment appears at the bottom; Note that the precipitate will fall out with each drop, but until a certain moment it will dissolve with stirring. If there is too much sediment - on the contrary, add alcohol.
Probably, it is also possible to calibrate the solution by the density, but a small deviation of the density from the required one does not affect the operation of the stormglass, so I did without this step.
Everything! The solution is ready! Fill it into a flask with a ground stopper (leave some air in the flask so that the solution can expand when heated), seal it with a sealant (I recommend taking silicone - the solution is sufficiently active, and, for example, I have dissolved the vacuum grease in my result), hang outside the window next to the thermometer - and watch for growing and dissolving crystals.
Enjoy watching!
In short, the stormglass is a flask with camphor solution used to observe the weather in the 19th century. There is a lot of information about him in the network - but the descriptions of the principle of operation usually boil down to the esoteric “I have not received a full scientific explanation.” A few years ago I read about the stormglass, became interested, made myself like this, experimented at home for several days, then hung the flask by the window and for the second year I observed its behavior in real conditions.
Such stormglasses sell on ebay - the crystals look beautiful, but by their appearance I can say that the stormglass was used idly, and the weather now does not show.
The explanation of the principle of operation turned out to be incredibly simple, and the device itself was sensitive enough so that I could, looking at it, understand how to dress when leaving home.
Stormglass is known largely due to Captain Fitzroy , the very one who drove Darwin on a world tour. In a nutshell, the stormglass is a solution of camphor in diluted alcohol, with the addition of inorganic salts. The solution is unstable, and when the weather conditions change, camphor crystals fall out of it, the number and form of which can be used to judge the weather.
I did not find any clear explanations of the principle of the stormglass operation on the Internet, but, in general, it was clear that the main "factors" of the weather are temperature, pressure, humidity, insolation, and, perhaps, something like an electromagnetic field. It is known that in old meteorological stations, stormglasses usually were sealed flasks, which means they could not measure pressure and humidity. In the visible part of the spectrum, the stormglass solution is transparent, and the ultraviolet glass flask does not let through well, so the reaction to sunlight is also unlikely. Eliminating the effect of electromagnetic fields on a solution or factors unknown to science was more difficult - but it still seemed to me most likely that the storm glass responds to temperature fluctuations.
My stormglass shows that it is cool and gradually getting colder.
I thought about all this before making my bottle. The first experiments showed me right. The fact is that the solubility of camphor in a mixture of alcohol and water strongly depends on temperature: it is enough to warm the solution slightly, and it becomes transparent, it is enough to cool it - and the whole flask will be filled with white camphor flakes. At the same time, the principle by which the composition of the solution was chosen was made clear: the ratio of the amounts of alcohol and water was taken so that in warm weather most of the camphor would dissolve, and in the cold it would precipitate; then, as the temperature changes, the amount of camphor flakes will change most noticeably. Mineral salts are needed in order to increase the density of the solution; due to the addition of these salts, the density of the solution is about the same
These were common words. Now a few observations:
- The most obvious fact: the amount of crystalline camphor at the bottom of the flask depends on the temperature. The colder, the thicker the layer. At the same time, over time, the deposited layer is compacted, so a dense layer at the bottom shows the approximate temperature of the last weeks, and by changing the thickness of the loose fresh layer it is easy to estimate how much colder it is today.
- With a slow cooling at the bottom of the flask, needle-shaped crystals begin to grow. When warming, on the contrary, the needles of the crystals dissolve, and the bottom layer looks like friable melting snow.
Slow cooling: a clear solution and camphor needles. The smaller the needles and the longer they are, the slower the temperature falls. Remember the first photo of a stormglass of mass production? There the needles are very long and beautiful - apparently, the storm glass was cooled very slowly and carefully - perhaps even in a thermostat. - With a faster cooling, camphor crystals precipitate not only at the bottom, but throughout the entire volume of the flask - they look like snowflakes hovering in thickness.
Moderately fast cold - it is snowing. - And when it gets cold quite quickly, even the snowflakes do not grow, the whole solution becomes cloudy at once and becomes similar to Schweppes.
Schweppes The solution in the storm glass class is muddy — it looks like this during a sharp cooling; on the bottom lies a yellowish layer of packed camphor; this layer is thin, that is, it is now quite warm.
In the comments, the question arose: "How is the size of the crystals related to the rate of temperature change?"
So, if you explain on the fingers,
то частицы всегда предпочитают встраиваться в крупные кристаллы (так же, как маленькие капельки воды предпочитают собираться в большие — так энергия поверхностного натяжения меньше). Если температура падает медленно, то молекулы успевают найти большие кристаллы и осесть на них. Если температура падает быстро, то у молекул нет времени найти большие кристаллы, и они осаждаются на первые попавшиеся — и получается много мелких кристалликов на дне. А если холодает совсем уж резко, то молекулы вообще не ищут кристаллы, а сливаются друг с другом, и возникает взвесь кристалликов камфоры в растворе.
Кстати, если потом долго ждать, то со временем молекулы могут перегруппироваться в крупные кристаллы — с этим связан рост кристаллов сахара в варенье, описанный в комментариях, и то, что весенний снег состоит не из снежинок, а из крупных кусочков льда.
Кстати, если потом долго ждать, то со временем молекулы могут перегруппироваться в крупные кристаллы — с этим связан рост кристаллов сахара в варенье, описанный в комментариях, и то, что весенний снег состоит не из снежинок, а из крупных кусочков льда.
Of course, to fully predict the weather, just observing the temperature dynamics is not enough - in fact, even modern meteorologists, who have the most powerful computers and a network of meteorological stations that enveloped the entire planet, are not very good at this task. But in the conditions of the beginning of the XIX century, when even the most banal thermograph seemed to be a high-tech device - and in sea conditions, when the thermograph had to somehow be protected from ship rolling, the stormglass functions were in demand.
Now a little about making a stormglass:
I took the recipe from Wikipedia as a basis:
10 g camphor (D-isomer or natural)
2.5 g of potash nitrate
2.5 g of ammonia
33 ml of distilled water
40 ml of alcohol.
Potassium nitrate and ammonia are potassium nitrate and ammonium chloride, respectively, you can buy them at the hardware store. 10% camphor solution is sold in a pharmacy.
The concentration of camphor is not very important - I read about stormglasses made directly from the pharmacy 10% solution. But, if you (like me) do not want to move too far from the recipe, add water to camphor's solution - camphor will immediately precipitate in the form of large dense flakes that are easy to filter (for example, with a nonwoven napkin), dry (note that Camphor evaporates during drying, and it should be taken with a margin) and dissolved in alcohol again, to the desired concentration.
If the salts you took in the hardware store, they are most likely dirty and should be recrystallized. This is also simple: take boiling water (better distilled from the auto parts store), pour so much salt into it so that it stops dissolving, defend the solution (or better filter it through the same non-woven napkin), cool it to room temperature, collect the fallen out bottom sediment salts and also dry it.
Now you mix the components in the right proportion, and get a semi-working stormglass.
Another stormglass with beautiful crystals. If your will stand in the room, and not hang outside the window, then something similar may grow in it.
“Conventionally” - because it also needs to be calibrated for your weather. This is a bit boring, but also easy: take the resulting mixture, slowly heat it to the temperature that you want to make the maximum operating temperature - for example, the temperature hanging outside your window shows on a moderately hot summer day. Now make sure that very little camphor remains at the bottom of the tank with the mixture: if camphor has dissolved all, with constant stirring, add water to the solution drop by drop until a little sediment appears at the bottom; Note that the precipitate will fall out with each drop, but until a certain moment it will dissolve with stirring. If there is too much sediment - on the contrary, add alcohol.
Probably, it is also possible to calibrate the solution by the density, but a small deviation of the density from the required one does not affect the operation of the stormglass, so I did without this step.
Everything! The solution is ready! Fill it into a flask with a ground stopper (leave some air in the flask so that the solution can expand when heated), seal it with a sealant (I recommend taking silicone - the solution is sufficiently active, and, for example, I have dissolved the vacuum grease in my result), hang outside the window next to the thermometer - and watch for growing and dissolving crystals.
Enjoy watching!