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Che Swa,} The Physiological Exhaustion and Vitality of Beer Yeast.
3rd 4th 5th
SCIENTIFIC AND ANALYTICAL
were formed, a few drops of creosote were added to the
water intended for washing. Every twenty-four hours CHEMISTRY.
the water was decanted and renewed by a fresh supply,
under the same conditions. All these washings were On the Physiological Exhaustion and the Vitality of screened from the air in an atmosphere of carbonic acid, Beer Yeast, by M. A. BECHAMP.*
the apparatus being in a warm place, the temperature of
which could vary from 20 to 30°. The life of the leaven being contained in the cellule, I
These washings furnished the following results :supposed that, so long as this cellule was neither destroyed nor dead, the leaven would continue to live, and to manifest this life by its characteristic chemical ist washing-anhydrous phosphoric acid.
0'056 actions, but in certain cases, such as those about to be 2nd
o'073 described, like an animal in a state of inanition—that is
0'074 to say, in exhausting itself.
0'076 To measure the physiological exhaustion of beer yeast,
0'444 I estimated the phosphoric acid it eliminates while con
o'371 suming its own tissues, when forced to live in distilled
o'190 water. Mitscherlich analysed beer yeast, and from his ana
Total of phosphoric acid . 16630 lysis concluded that 100 grammes of dry yeast contain the elements of 4*28 gr. of anhydrous phosphoric acid. merely an inert precipitate, were phosphoric acid
These numbers appear significant. Were beer yeast But this analysis does not prove that the acid was actually present in the mass, as mother liquor is in a precipitate, formed there. The infusion of yeast is, no doubt, always acid, and this soluble matters in the first operations, and the quantity
The washings would eliminate the greater part of the acidity may be attributed to phosphoric acid, if the yeast of these matters would diminish more and more. But does not ceaselessly engender other acids. Toascertain that the yeast actually contained preformed phosphoric acid, its resistance diminishes, and it yields a large quantity
we see here that the yeast at first resists, then suddenly and phosphates, boil the well-washed yeast in a large of its disassimilated materials. This is ascertained by the quantity of distilled water ; this will kill it, and cause it weight of the phosphoric acid eliminated, which sudto abandon rarious products, and among them phosphoric denly increases to five or six times its previous weight ; acid, which estimate by the process presently to be de- after which it naturally decreases. scribed, whence it will be found that soo grammes of dry yeast disengages from 2.8 gr. to 3's gr. of phosphoric 100% of the phosphoric acid in dry yeast, the number
By adding the amount of the different estimations at acid, of which a portion is free. But though the yeast abandons large quantities of acid eliminated is then greater by i than that produced
will be found to be 3:38. The weight of phosphoric phosphoric acid, at a temperature of 100°, when it is killed, this is not the case when it is left in water, either by the incineration of the yeast, as in Mitscherlich's cold or even heated to 30 or 40°; under these circum- process; and if it is observed that the yeast eliminates stances it abandons the phosphoric acid and other matters to the quantity of phosphoric acid, an idea may be
at the same time various other products, proportionately very gradually, not as an inert precipitate, but as a formed of the degree of exhaustion undergone by each living creature, offering vital resistance to destruction, globule. The exhaustion is such that under the microBy renewing the water every twenty-four hours, and scope the yeast seems reduced to merely its envelope ; it estimating the phosphoric acid in each lixivium, it will is then barely visible, and its colour so faint that it looks be found that the quantity of this acid, small at first, like shrivelled skins, with no clear outlines, and with a augments with each successive treatment, and rapidly taste like raspberries. From the nuclei or interior attains a maximum, after which it decreases, until it granulations which remain, the form of the envelope altogether disappears. The following is the experiment:
may be divined. In the first place I determined the amount of phos
If by the use of the apparatus, elsewhere to be de. phoric acid which could be found in matters adhering to scribed, the air is perfectly excluded, this exhaustion the yeast, proceeding from the medium in which the can be effected, without what is called the putrefaction yeast was formed, or which had been excreted by the of the yeast, or, more correctly, without the appearance yeast itself and impregnated it externally. soo grammes of the organisms which cause the putrefaction of the of brewers' yeast, new and in a paste, were soaked in organic matters eliminated. But if air enters, these cold water and washed on a filter. The yeast having products acquire a fætid odour, and there may be obbeen well drained, there remained four litres of lixi- served a disengagement of sulphuretted hydrogen, and vium. In this liquid the phosphoric acid was esti- the formation of the infusoria, which are the cause of a mated by the same process which was applied to the particular fermentation of the nitrogenised and sulfollowing estimations; and there were obtained of phuretted organic matters of yeast. However, if the anhydrous phosphoric acid, oʻ095. gr. This result is invariable; all things being equal, 500 ferent, the quantity of the latter in each washing cor
other products accompanying phosphoric acid are difgrammes of yeast in a paste, representing about 100 responds to the numbers of the above table. grammes of dry yeast, yield to cold water less than ,
The yeast exhausted in the experiment which furdecigramme of phosphoric acid.
nished the numbers given in the table appeared to be 280 gramries of this game washed yeast, containing dead; but this was not the case, for it was still capable 4862. gr. of yeast dried at 100°, were introduced into a of transforming cane sugar into glucose—that is to say, special apparatus with 1600 cubic centimetres of water of forming zymase and then producing alcohol by the boiled and then cooled to 40° in a current of carbonic glucose engendered. But the products
of alcoholic feracid. To make perfectly sure that no foreign bodies mentation by exhausted yeast are notably different in * Comptes Rendu, lxi., 689.
nature and in quantity from those obtained by normal YOL. XII. No. 314.-DECEMBER 8, 1865.
CHEMICAL News, 268 An Account of Bird's Water-Barometer.
Dec. 8, 1865. yeast. The same as in alcoholic fermentation by mother I have tried various oxidising agents, but have found of vinegar, a crystallisable compound is formed pos- none better or more manageable than bichromate of sessing the properties of mannite.
potash.-Pharmaceutical Journal. These results prove contrary to Mitscherlich (who supposed that the globules of ferment, well washed in
PHYSICAL SCIENCE. water are entirely deprived of the property of saccharifying cane sugar), that yeast continues to change cane sugar until it ceases to live, and that when it is so much An Account of the Water-Barometer Constructed and exhausted that it may be said to be reduced to its cellule,
Erected by ALFRED BIRD, Experimental Chemist, it nevertheless continues to form successively glucose and
Biriningham. alcohol with cane sugar. The property of determining I have the pleasure to send for insertion in the Chealcoholic fermentation must not, then, be attributed to MICAL News an account of a water-barometer, which I the catalyic action of some chemical compound which it have had in perfect action for six years. It was shown contains'; my researches seem to prove that it is con- to the members of the British Association on their visit tained in the properties of the living cellule ; it is a to Birmingham, and a general desire having been ex. consequence of the act of nutrition of this cellule.t
pressed that an account of the instrument should be
published, I send you the following particulars and Detection of Methylic Alcohol, by Mr. JOHN T. Miller. drawings :
In the construction of a water-barometer four things The following modification of my process for the detec. have to be attended to,tion of methylic alcohol may be used when it is wished
ist. The water must be deprived of air. to avoid distillation. It is easy of execution, and gives 2nd. The air must not again enter the water. very fair results :
3rd. The water must go into the barometer, to the ex. Prepare in a small flask an oxidising solution with clusion of the air; and 20 grains of bichromate of potash, 3 fluid drachms of 4th. The instrument must be so constructed that, water, and 20 minims of strong sulphuric acid, and add while the atmospheric pressure within the instrument to it 30 minims of the spirit to be tested. After the shall be uninterrupted, no air shall penetrate into the mixture has stood ten minutes, add just enough milk of vacuum-chamber. lime to give it an alkaline reaction ; warm, filter, and I will begin by describing the material. The tube is wash with half an ounce of warm water. The filtrate composed of metal and glass, and the three taps are will be free from chromic oxide and the greater part of those known as “ Lambert taps.” The size of the metal the sulphuric acid. Precipitate the remainder of the part is half an inch internal diameter, and is that sort of latter, and any chromic acid which may be present, by white-metal tube which is in universal use by gasthe addition in small excess of a strong solution of fitters, called “compo.” I believe it is an alloy of lead acetate of lead; warm slightly, allow a few moments for and zinc. the precipitate to subside, and filter. The filtrate should
I recommend the compo tube made by Messrs. Stock, now be clear, colourless, and nearly neutral to test-paper. Brothers, and Co., in Birmingham, as it will stand an Boil it quickly down to 2 fluid drachms, pour it into an internal pressure of fifty pounds of air to the inch withounce test-tube, add 1 drop of dilute acetic acid (1 part out leaking. The glass tube to show the “ readings ” is of the B. P. acid to 2 parts water), and 1 grain of one inch internal diameter and six feet long. The brass nitrate of silver in 30 minims of water; then heat the Lambert taps are half an inch internal diameter. These liquor slowly to the boiling point, and simmer two or taps are constructed internally with a cushion of india, three minutes. Darkening of the solution to a con rubber, pressed down by means of a brass plate acted siderable degree may occur even though the spirit be upon by a screw, which makes them absolutely secure. free from methylic alcohol, and is, therefore, a less I will next describe the upper and lower parts of the reliable indication of the presence of that substance barometer in reference to the drawings. Plate 4. AA is than when the oxidation products have been separated the compo tube, having two enlarged sockets B, B, one by distillation. The state of the test-tube will, however, and a half inch in diameter and three inches deep. These decide the question. It should be rinsed out, filled with sockets were made of brass, and their office is to receive water, and placed against white paper. If it appear the ends of the glass tube. To fix the glass tube C, about clean and uncoloured, the spirit is either pure or contains six inches of the compo tube was soldered to the bottom less than 2 per cent. of methylic alcohol ; if
, on the of the socket, and being inverted and fixed very steady: other hand, the lower part of the tube have an evident enough dry sand was poured into the compo tube to fill brown tint, the spirit is methylated.
it up to the bottom of the socket B. The use of the To obtain satisfactory results by this process, the sand is to prevent the cement from running into and points to be minded are :- 1. To use distilled water. stopping up the compo tube. The glass tube C, per2. To add only a slight excess of the precipitants. 3. To fectly clean inside, was now placed in the socket; and use a perfectly clean test-tube. 4. To avoid boiling the being most carefully stendied to keep it upright, six liquor up the tube, and so thinning the metallic deposit inches of dry sand were poured down to keep the cement by spreading it over a larger surface.
from rising up the glass tube C. + These conclusions are opposed to M. Liebig's assertion (Traite de
The cement was composed of two parts of gutta Chimie organique, introduction p. 27) :=" The insoluble body called percha and one part of common black pitch. These two
ferment does not provoke fermentation.” The proof he gives of substances were heated in an iron ladle with a lip, till this is, that the yeast washed with water, deprived of air, leaves a residue which has lost the power of fermenting cane sugar, This they became perfectly fluid and quito free from froth. A has caused it erroneously to be supposed that the phenomenon being "copper bit" used by plumbers having been heated to much less decided bad censed to exist at all. On the other hand low soldering-heat, a small quantity of the cement was bably unknown experiment of M. Dubrunfant) that M. Pasteur has to the outside, the effect being to perfectly liquefy the sugar, and it is well known (notwithstanding an important and pro- ponred into the socket. The copper bit was then applied admitted that cane sugar ferments directly, the formation of changed | cement in situ. A little more of the hot cement was 269
An Account of Bird's Water-Barometer.
A place being chosen on the staircase of my house, a flat board seven feet long and one foot wide, was fastened to the wall, upon which board was fixed the socketed glass tube C, and graduated scale F, from the top of which 422 inches were most carefully measured down to the “zero ".point E beside the cistern.
The scale F is to the right of the glass tube. It is made of well-seasoned boxwood, and is graduated to inches and tenths. The sliding-tube G, with the vernier H, is between the glass tube and the boxwood scale F. On the left side of the glass tube C is another slidingtube y, with a vernier ), to record position of top of tidal colamn of water at 9 a.m. the morning previously.
The glass tube, scale, and verniers having been securely placed on the board and perfectly upright, the gas-fitter proceeded to connect, by soldering, the renainder of the compo tube above the glass tube C, which was continued upwards till it entered nearly at the bottom into a round vessel K, made of zinc, four inches in diameter and eighteen inches high. Inside the vessel the tube coils round in a spiral, like the worm of a still. This vessel and spiral are not necessary to the action of the barometer ; but as the spiral is in the part of the tube in which is the vacuum-chamber, it gives the opportunity of artificially cooling with ice or snow the included aqueous vapour, and thus determining by actual experiment the amount of correction required. If the experiment of cooling the included vapour to
АУ 32° be tried in suramer, when the external temperature is 70° or 80°, the sudden cooling causes so great an evaporation from the surace of the water, and condensation in the upper part of the barometer, that a real rain-shower is produced, the condensed water running down the glass tube in innumerable pellucid drops in the most beautiful manner, thus perfectly imitating the condensation of invisible watery vapour in the higher regions of the atmosphere. When the compo tube leaves the zinc vessel, it is led up perpendicularly to the Lambert tap L. Above the tap I the tube still rises perpendicularly, when it suddenly bends down, leaving the end
open at M.
I now describe the part of the barometer below the
The compo tube being soldered on, was carried down to the cistern, not necessarily perpendicularly; for instance, the tube may descend at an angle of 30° or 40°, and may be led in any convenient direction. The entire instrument erected by me is inside the house, to escape a freezing temperature. At the lowest bend of the compo tube is a short upright tube, having at the end a Lambert tap N, to which is soldered a male screw of a th-inch gas union-joint O, the use of which will be understood further on. The compo tube now begins to ascend; and at the top of the bend is another Lambert tap P. Beyond this the compo tube bends down and reaches nearly to the bottom of the cistern, which is a one-gallon white glass narrow-mouth upright bottle R. The bottle rests upon a stand S, which mores up and down by means of a set screw T, acting through a stout shelf U U; and the bottle is kept steady by means of the two
CHEMICAL NEWS, 270 An Account of Bird's Water-Barometer.
Dec. 8, 1865. uprights W, W, upon one of which is fixed the zero- water was 400 inches high, the mercurial barometer being point E.
30'4 inches, and the temperature 67o. I shall now describe the method of filling the baro- In order to see whether gaseous matter would accumeter. Four gallons of water were carefully distilled, mulate in the vacuum chamber, the gutta percha syphon and being put into a perfectly clean and new tin oil-can was allowed to remain in its place for some weeks, and with a narrow mouth, the water vas boiled for one four different times tap P was closed, tap N opened, with hour over a bright fire, to drive out the air. While still tap 2, thus filling the barometer up to tap L at top, boiling, two quarts of olive oil were poured in. This which being opened allowed the water and gaseous slightly increased the pressure in the water underneath, matter, if there had been any, to flow out at ^. On causing the last remains of the air to rise with the steam closing tap L and tap N and opening tap P, the column in jets or spirts through the stratum of oil. The instant of water again fell; and after syphoning out the surplus ebullition was stopped, the oil closed over the boiled water from under the oil in the cistern till the oil was water, and it became hermetically sealed from the atmo-level with the zero-point E, the column of water was sphere. The contents of the tin can were now cooled, found on the four different trials to be exactly the same and the can X was placed above the top of the water height on the scale after each trial as before. It was, barometer. A piece of gth-inch gutta-percha tube Y Y, therefore, plain that no gaseous matter had accumulated sufficiently long to reach from the can X above to below above the water, and that, with the exception of the vapour the very bottom of the barometer, was procured, and of water, it was a perfect vacuum. one end of the tube was put into the mouth of the can X, One or two precautions are required in order to ensure the end passing through the supernatant stratum of oil success. In the first place, the water must be distilleddown to the bottom of the water underneath. At the for if the water contains “ earthy salines" or colouring other end of the gutta-percha pipe Y is a gth-inch tap, matter, it is certain, by the constant evaporation and terminating with a th-inch female screw union-joint 2. precipitation in the working part of the glass tube, to The gutta-percha pipe being in position, and hanging crust it over so completely, that in a few months the down as seen in the drawing, became a syphon; and water becomes invisible; pure distilled water is, therethe air being sucked out, the water at once came over, fore, indispensable. Then, if the slightest leak in the and was stopped from running away by turning the barometer exists, it will infallibly bring the instrument small tap 2. The female union-screw at Z being tightly to grief. In order, therefore, to be sure that the baroscrewed on to the male screw-joint O, the water was meter was sound (before the water deprived of air ready to enter the barometer.
was put in), I closed tap L at top and tap P; then, The first thing to be done was to displace the air in connecting the gutta percha tube with the street waterthe bend of the tube, reaching from the tap N at the works” pressure, I allowed it to enter the barometer till bottom to the extreme end of the compo tube in the the included air was contracted to one-fourth of its length cistern R. This was done in the following manner :- having a pressure of water under it of between 40 and The cistern or bottle was taken away and filled quite 50 lbs. to the inch. full to the very brim with best olive oil; the three The barometer stood this internal pressure for ten Lambert taps being all open, and the bottom end of the hours without the air being forced out. I therefore con"compo” tube hanging down, the small gas-tap Z was cluded that if the barometer would stand this great presopened ; the water then began to ascend both legs of sure inside, it would stand 14 lbs. to the inch pressure the barometer, and when it reached the tap P, it passed on the outside, and without hesitation I filled it with the over and ran out of the end of the tube which was prepared water. hanging down. At that instant the stream was stopped As the instrument is made by a gasfitter, it would be with the thumb, and, the tap Z being turned off, the easy to put the whole of it together, Lambert taps inbottle full of oil was brought to the thumb which cluded, and to prove it with some powerful water-presstopped the end of the compo tube and kept in the sure before the instrument is taken to the place where it water. The thumb supporting the tube was now put is to be erected. Also the water deprived of air and into the oil, and the end of the tube slipped down to the covered with a stratum of olive oil in the tiu can could bottom of the oil. The bottle was then put into its place be sent, if necessary, 100 miles away without the possion the stand S, and the surplus oil being syphoned out, bility of any air getting into it. If a gutta percha pipe there remained in the cistern R about three inches in is not to bé had to fill the barometer, a piece of compo depth of olive oil, the compo pipe dipping into it nearly tube will answer every purpose, which, when done with, to the bottom.
is none the worse for gasfitting purposes. The next thing was to fill the longer part of the baro- I shall conclude with some account of the action meter, which was accomplished as follows :—The tap P of the water barometer. In the Philosophical Transbeing closed and the small tap Z opened, the water actions for 1832 is a description by Mr. Daniell of rapidly rose in the barometer; when the water had a water barometer which he erected at the Royal reached the opening M at the top, it was allowed to run Society's Rooms, at Somerset House, which was in a minute or two to carry any traces of air away which action for two years, but afterwards got out of order. might have lingered in the tube. Tap L at the top, and in describing the action, Mr. Daniell states that “the tap N at the bottom being then securely closed, tap P water appears to be in perpetual motion, resembling the was opened, and the column of water began to descend slow action of respiration." and to accumulate in the cistern R under the stratum of I can fully corroborate Mr. Daniell in this parti. olive oil. As the column fell it was narrowly watched cular, and from careful and continued observation am in the glass tube, but not a bubble of gaseous matter was able to state that the times of the oscillations are observed. On examining the cistern R, it was found about every four minutes and twenty seconds. It is that the oil did not quite reach the zero-point E, more requisite to watch the oscillations with a magnifier, oil therefore was poured in till the zero-point E and the as they vary from the twentieth to the thirtieth part level of the oil were coincident. The graduated scale of an inch, which distance can be well observed when was now looked at, and it showed that the column of magnified.' But the most surprising oscillations in the
271 water barometer are during a thunderstorm accompanied Since Sir John Herschel proposed his new theorywith great falls of hail and heavy rain drops. I have that the disruptive electric discharge is the result, and given a chart of five minutes' readings for one hour and not the cause, of the sudden condensation of cloud into five minutes during a heavy thunderstorm from the “rain drops,” in consequence of the cloud coming in connorth-east, which passed over Birmingham July 20, tact with an extremely cold and dry current of air--it 1859. The upper curred line shows the water oscilla has occurred to me that the sudden increase in the tions, and the lower curved line shows the oscillations in density of the air, as shown by the rise of the waterthe mercurial barometer. The temperature is recorded column, may be due to the sudden precipitation of rainat the foot. It will be observed that while the water drops of unusual size, leaving the atmosphere drier and column rose and fell in a most surprising manner, the consequently denser; it being well established that the mercurial column showed hardly any motion, which was mercurial column is always high when the air is dry, of a laggard character.
and vice versa. At 4.20 p.m. the storm reached its climax, the heavens
I conclude this account of the water-barometer by grew darker overhead, and the water rapidly descended, stating that the object with which it is written is to give causing a most impressive feeling on the mind, when practical directions for the construction of these noble suddenly came a terrific blaze of lightning, instantly instruments with a view to their becoming common for followed by the " thunder cannonade” (if I may so call the furtherance of meteorological science. it); then down came the hail and heavy rain, and as the sky began to brighten the water commenced to rise, and
The total cost of the materials need not exceed 31., in the next five minutes it had risen more than four- exclusive of gas-fitter's time. tenths of an inch.
Birmingham, November 14,
ning, rain, but Barothunder; thunder;
no wind. meter.
thunder rain ;
29 Temp. F. 75 740 74 74
74° 74 75 75° 75" 7+
74 74 Chart of one hour and five minutes' readings of the Tidal Oscillations in the Water Barometer, during Thunder storm, July 20th, 1859.
which have a special reference to digestion and respiraPROCEEDINGS OF SOCIETIES.
tion ; and, secondly, those which have a more immediate
connection with the human system in their direct action SOCIETY OF ARTS.
as therapeutic agents.
DIGESTION.-Man requires several varieties of food to CANTOR LECTURES. « On some of the most important Chemical Discoveries made the most important of these is atmospheric air, which is
maintain the health and strength of the body. One of within the last Two Years."
chiefly used to maintain the heat of the body so essential By Dr. F. CRACE CALVERT, F.R.S., F.C.S.
to vitality, by oxidising the various substances taken as
food, or by oxidising the tissues which have been destroyed LECTURE 3.
in the body by the wear and tear of life, and which, Tuesday, April 18, 1865.
having fulfilled their functions, require to be removed, that . On the Discoveries in Physiological Chemistry.-I intend new tissues may replace those which have disappeared. in this lecture only to give you a general outline of some The next class of food which man requires are fluids, of the main facts connected with the phenomena of diges which are chiefly represented by water, either pure or tion and respiration, introducing as I proceed some of the mixed with other substances, and which fulfil in the body most important chemical facts connected with that branch two principal functions—that of carrying into the stomach of science discovered or observed within the last two years. and the intestines various nutritious elements which have To enable you to appreciate more fully the importance of been taken as food, and conveying them into the blood by those discoveries, I shall divide my lecture under two 'endosmosis, or the force called by Mr. Thomas Graham, principal heads-first, the studying with you those facts | the Master of the Mint, " diffusiori."