Louis PASTEUR (1822-1895). Autograph manuscript, February-Ma - Lot 527

Louis PASTEUR (1822-1895). Autograph manuscript, February-March [ca. 1856-1860?]; 8pages small in-4 (23.5x18cm; some stains). Leaves from experimental notebooks on fermentations. These notes record experiments carried out from February 1 to March 17, and probably relate to research on alcoholic fermentation, which led to the two memoirs on tartaric acid fermentation (1858) and alcoholic fermentation (1859), already announcing research on so-called spontaneous generations. These fragments of a laboratory notebook comprise one bifeuillet and 2 single sheets; the notes are written in very fine black ink, with a few calculations in pencil. The sheets bear some original stains, notably the trace of a vase placed directly on the paper. Quantities of measurements are interspersed with observations and reflections on experiments. "February/ Sulf. of potash 0,2 Magnesia 0,2 Sulf. of iron 0,1 [...] This experiment is as conclusive as possible. [...] I sieved the liquid N.1, and this operation seems to have introduced A2 again. No further sieving is necessary. [...] [P. 19] N.1 Water 1500 Ac. Tartaric acid 0.7 [...] Potassium phosphate [...] I add ordinary air to N.1 and purified air to N.4. The N.7 liquor has become acidic; yesterday it was 10 Mars ammoniacal. So there's a fixed acid. Total volume of N.7 1260cc. I evaporate 250cc in a bain-marie. I put 1000cc back in the oven. There must be a total of 46 gr (acid + sugar) [...]. February/ Sulf. of potash 0,1 sulf. of iron 0,1 Magnesia 0,1 - air purified by So3 and Ko. [...] is not successful, since in N.3 the weight is as high as in N.2, and the vegetation languishes. I sifted and the vegetation started to grow again. The vegetation no longer needs to languish, so I add N.4 [...] Let's assume that acid is part of the material that reduces the liquor [...]. I added N.5. sugar. Water residue and excess matter - it grew back. [...] March 12. Added 30g sugar to N.4.3. [...] March 17. Nothing grew back. [...] Assuming even the most unfavorable circumstances, the equivalent of 6gr of So3Ho must have formed in vase N.1. But it's likely that there is much more, at least 10 g, which is equivalent to 5 or 20 g of organic acid. [...] 4 Mars [...] N.1 has grown the most. But nothing can be concluded from this, because when I added A2H3, a film had already formed on the surface. But it remained white, whereas in the other vases, the film blackened and fructified. This hasty maturation and the disturbance caused by agitation may be the causes of these differences. February 11. I added N.1 1 gr of pulverized terrine. [...] I added a little magnesia 2 or 3 days after the 11th. [P. 13] N.1 Water 3000 Am nitrate 0. Tartaric acid 1.5. Potassium phosphate 0.8 [...] On March 7th I added N.5 sugar 40 gr; on the 8th I added more mixture [...] The N.5 seems to be picking up. I'm going to add N.6 mineral matter, then see if it picks up again. I must also find out if all the sugar has disappeared in the stopped vases. [...] Why has all this vegetation almost ceased to grow? [...] 1° Let's assume that the acid does not reduce the cupric liquor [...] Add as much N.5 as you need. If it grows, it was missing something. If not, there's a harmful substance."