Mendeleev
 
While in St. Petersburg we decided to try to find Demitri Mendeleev's laboratory.  He was the scientist who had discovered the periodic table which brought order to the science of chemistry.  While we were on a driving tour of the city our guide pointed out Mendeleev's statue outside the the university where his lab was located.  We had no problem finding the building again when we were on our own. 
Now our problems began.  There were no signs indicating where the lab was in the building.  Actually it was a complex of university buildings with no signs on any of them.  We asked someone who was passing by.  We of course couldn't ask in Russian and they didn't speak English.  They did understand us well enough to lead us to a door in a dark hallway which we had walked past in the first building we entered.  They pointed to the unmarked door and left.  We tried the door.  It was locked.  Not knowing quite what to do we were standing there when Nancy noticed what appeared to be an ornate doorbell button that had been painted over many times.  We tried it and heard a bell ringing inside.   The door soon opened and we were met by a woman who of course spoke to us in Russian.  We indicated we didn't understand.  She said "Francais?"   We said "Niet, English."  She said "Deutsch?"  Again niet.   She tried a couple more languages then shrugged, said something we took to be "Sorry." and began to close the door.  We protested and pointed out the shirt and socks I was wearing (both had a copy of the periodic table) and asked if we could just look around.  She gave a little laugh and ushered us inside. 
We found ourselves in a rather small museum which had been his lab and office.  As we started to look around she pointed out a picture on the wall and named the people in it.  They were scientists that I had heard of so I nodded and apparently looked like I understood.   So began our tour narrated entirely in Russian.  There are a remarkable number of technical words that when said in Russian sound like English spoken with a strong Russian accent.  That, plus being able to recognize equipment and materials Mendeleev used, a lot of gestures, and her patience with us resulted in a very educational and enjoyable tour.  I shouldn't leave you with the impression that we understood everything though.   At one exhibit our guide, apparently encouraged by our interest, launched into an extended discourse.  I was straining to pick up something which I recognized.  She could see that I wasn't getting it and tried again, and again, and again.   Finally Nancy 's eyes brightened as she said "Ahhh!"  As we were lead to the next exhibit I asked Nancy what our guide had said.  Nancy replied very quietly that she had no idea but it was clear that our guide was going to keep explaining till we understood and that was the only way we would see the rest of his lab. 

This statue wasn't far from his lab but we would have been looking for a long time if that was our only clue to its location.   The wall next to the statue displayed the periodic table of the elements.  The symbols for the ones he predicted would be discovered are shown in blue.
   

Here is our guide pointing out Mendeleev with some of the famous scientists of the day.  The second picture shows him with some of his students.  In the last he is at his lab desk pondering the puzzle of how to make a logical arrangement of the 63 elements that were then known.
    

Here are several of the periodic tables that were on display.  If you look closely at the first handwritten one you will see chemical symbols and atomic weights.  Note the question marks next to some entries.  If there is no chemical symbol it indicates his predicted weight for an element yet to be discovered.   Much has been made of those predictions but what is as impressive to me is the symbols and weight pairs he questioned.  Those question marks were saying that he thought his theory was better than the work of scientists who had made those determinations.  That strikes me a rather nervy.  By the way I checked some of them and Mendeleev was right.
  

Here is a printed version of his table with some of the blanks filled in as the elements were found.  The second table shows some of his notes that helped convince him that there were elements yet to be discovered.
   

I wasn't able to figure out just what this diagram was showing.  There are 7 sectors with numbered circles in them and lines connecting some of them.  The sectors could correspond to the columns of the periodic table (minus the noble gases which were unknown at that time) but the numbers don't seem to match up with atomic weights.  There are notations in Russian that would help to understand it I am sure but since I read Russian at an early first grade level I will need some help.  If you know Russian or chemistry and would like to try just click the picture for a high resolution version and then let me know what you figure out.  The label at the bottom says something about a (logical topic/theory? scheme) and I can't translate the rest.


Some of his chemicals on display.  I didn't try to read many of the labels but that purple one in the center says it is K Cl O4 which I think should be a white crystal.  Maybe I missed a letter or two in the formula.
When I saw these I couldn't help thinking about the chemicals that were in Edison's lab in New Jersey.  Not long after I visited it, many years ago, they discovered there were many bottles of toxic and/or potentially explosive chemicals there.  I wonder if these have been checked.
       

If you were doing chemistry research in the 1860's you may have been working with minerals to see if you could isolate new chemicals and if you were very lucky or very good new elements.  How would you know if you had been successful?  Only by checking the properties after you had purified it and comparing those with all of those then known.  The shape of the crystals that are formed is one of those properties.  Here we see 2 mineral samples and 3 common crystal forms that were on display.
  

Equal volumes of gases contain the same number of atoms (if they are the same pressure and temperature).  This provides a way to compare the atomic weight of some elements.  All we have to do is accurately measure the volume, weight, temperature, and pressure of  the element in gaseous form.  If they aren't gases maybe a compound of the unknown with other already known elements is.  Measure that compound and do some arithmetic and you have the atomic weight of the unknown.  What if you can't find any compounds that are gases.  You could try to measure the amount of some material that you have already characterized it takes to completely react with your unknown sample.  If you do that accurately, and can figure out the chemical formulas for the reactants and the product, and measure the weights of each, and do more arithmetic you have the atomic weight of your unknown. 
Simple, right!
To do any of this you used a lot of precision apparatus.  Glass tubes to hold the gases connected to other tubes of liquids so that pressures and volumes can be measured.  Scales (balances) of many types to permit you to weigh solids liquids and gases.  Some of these were invented or improved by Mendeleev and their design was published, for some he followed the designs of others. 
      

I 'm not sure just what this apparatus is.  My best guess is that it was used to separate crude oil into different fractions based on their volatility.
 

Some of the special purpose glassware on display. 
  

Two balances.  The second was used to compare the weights of equal volumes of gas.  Because the glass containers are the same size they automatically compensate for atmospheric buoyancy. 
   

Two slow pendulums.  They may have been used to measure equal time intervals so that reaction kinetics could be studied.
      

The column of this instrument had a finely ruled scale.  The device on it could be moved and its height accurately determined.  There was also what appeared to be a small telescope.
My best guess is that this was used to measure the change in the level of the liquid in the glass tubes without requiring all of them to be scribed with scales.  This would ensure accuracy and save a lot of effort in the production of the tubes.
  

This seemed to be a transit minus the telescope.  I can't figure out just what it was used for in a chemistry lab.


Here is Mendeleev's office.  We saw reference books in Russian, French, German and other languages.  One in English was from the Franklin institute in Philadelphia.  Pictures of famous scientists were on the wall behind him.  A chess set was ready for a game and this glass sphere tetrahedron was displayed on his desk.
     

Photography and painting were hobbies.  Here is his camera and some of the pictures he took.  All photographers in those days were chemists but they didn't have Mendeleev's expertise.
 

Mendeleev traveled through much of Europe and also the the United States.  The map shows places he visited to teach, and to meet with other scientists to learn what they had been working on.
His notebook entries show some of the places he visited in the US.  The stop in Oil City was especially interesting to Nancy and I since it is only a few miles from where we grew up.
  

A couple of bearded scientists.  The one on the right is the famous one. 



This little museum was a highlight of our trip to Russia.
If you want more information or can help me to understand more of what I saw I would like to hear from you. 

More of our trip to Russia
  St. Petersburg
  Moscow

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