50 Extract of a Letier from Berzelius to Gilbert. (Jury, 
You ask me to examine what Gay-Lussac has advanced respecting 
the nitrous gas eudiometer, and to repeat the experiments on which 
his method is founded, because they are in opposition to my views 
relative to nitric and nitrous acids. I acknowledge that I feel no 
inclination to undertake such a task. I am always averse to disputes; 
and if I were to engage in one, it must be of such a nature that it 
could be fully resolved by experiment. ‘This is not the case with 
Gay-Lussac’s experiments. Dalton has already shown, with toler- 
able accuracy, that according as there is an excess of nitrous or 
oxygen gas, a maximum or minimum of nitrous gas will be ab- 
sorbed, both measured by the quantity of oxygen gas which is like- 
wise absorbed. On this maximum or minimum usually depends 
the formation of pure nitric or nitrous acid. The question, there- 
fore, comes to this: whether between these two points there are 
gradations, consisting of combinations of determinate proportions 
of nitric and nitrous acids, or not; and likewise whether the results 
of Gay-Lussac be those which he really obtained, or whether he did 
not correct them by his views of true theory. The solution of these 
questions is attended with too much difficulty for me to bestow upon 
them the time that would be required for their examination. 
M. Avogrado’s remarks upon my electro-chemical theory I have 
already read in the Annales de Chimie. He appears not to know 
the treatise on the chemical action of the electrical pile by Hisinger 
and myself. His remarks upon my use of the terms electro-positive 
and electro-negative are correct. They had been already anticipated 
in your Annals, on occasion of my experiments and those of Davy. 
1 had changed them for others long before Avogrado’s paper ap- 
peared, as may be seen from my papers published in England. 
Some additions to the electro-chemical theory, which these papers 
contain, and which hitherto are unknown both in Germany and 
France, are perhaps worthy of your attention. You will find them 
in my treatise on the Cause of Chemical Proportions. 
Van Mons has communicated to me the discovery that he has 
decomposed the fluates at a red heat by means of hydrogen, and 
obtained compounds of fluoric acids and metals destitute of oxygen. 
Certainly this is strange. It ought likewise to be inaccurate, accord- 
ing to his preconceived opinions. Has he obtained a fluoric oxide, 
or a compound of flworicum with metals? Had he given me the 
names of the salts on which he made his experiments, it would have 
been easy to have investigated the subject. But I must wait fora 
more accurate account of his experiments, which he has promised 
me, before I can repeat them. 
You say to me that different persons wish that I would give an 
example how I make accurate chemical analyses on a small scale. 
This would be a difficult task; for I believe that I possess no other 
method or greater dexterity than other chemists. I seldom work 
upon a small scale. Most of my analyses are performed with ten 
or five grammes, that is to say, with 160 or SO Nurnberg medicinal 
grains (154°44 and 77°22 grains troy) ; and this I believe is the best 
