Imatges de pàgina


May 3, 1862. *

The Theory of Spontaneous Generation.


sufficient to furnish germs suitable to be developed in These experiments show that the air from elevated two or three days.

| localities is remarkably free from those germs which give It appears that the organic productions in the flasks origin to organic products. are more various than if the contact with the air had In collecting air for these experiments the following been free, i.e., the organisms in the several flasks are precautions were adopted to avoid as far as possible the different. This result might have been expected, for by intervention of dust carried by the operator or deposited limiting the rush of air and repeating it with different on the outside of the flask or other implements required flasks, a small number of germs would be collected in a in performing the experiments. The elongated neck of limited portion of air, and the growth of these germs the flask was first heated in the flame of a lamp, and a would not be obstructed by other germs, more numerous scratch was made upon the glass with a file. The flask or more vigorous or rapid in their growth, capable of was then raised above the head with the end of the neck monopolising the soil to the exclusion of those less turned towards the wind, and the point was broken off vigorous or less rapid in growth,

with long iron forceps, the branches of which had preIt was found that the number of negative results viously passed through flame to destroy any dust adhervaried greatly with the atmospheric conditions, and that ing to their surface, so that it might not remain to be nothing was easier than to increase or diminish the rela driven into the flask by the sudden rush of air when the tive proportion of flasks which gave birth to the organ- | point of the flask was broken. Great pains were taken isms mentioned, or the number in which they were | lest the agitation of the liquid in the flasks during transit totally absent.

might exert some influence unfavourable to the developIn the cellars of the Observatory at Paris, so situated ment of infusoria or mucedines. as to have very little change of temperature, and where The following results are therefore without objection, the air was remarkably quiet, the proportionate number and they show the entire difference between the air of of flasks that were opened in that locality without pro- | the plain or of elevations and that of inhabited places. ducing any organisms was much greater than for the Pasteur's first experiment at the Glacier des Bois was same number of flasks opened in the court-yard of the interrupted by a circumstance which has not been foreObservatory, where the air was constantly agitated. seen. He had taken to close the points of the flasks,

The explanation of this difference is obvious. Although after they were filled with air, an eolipile lamp fed with the air of the cellars of the Observatory, nearly satu alcohol. The whiteness and glare of the ice, in the light rated with moisture, was more fitted for the production of the sun, was so great that it was impossible to see of the various kinds of mould and infusoria than the the jet of alcohol flame, and as it was agitated by the open air of the court-yard, yet the stillness of the air wind it could not be directed upon the glass with suffiin the cellars allowed all ova and spores to be deposited cient steadiness to melt the point and hermetically seal by the force of gravity, and few or none remained float- the flask. As no means were at hand to render the ing in the air which rushed into the flasks opened in that flame visible, the flask could not be sealed, and there locality. In proportion as more precautions were taken remained chances of error by the admixture of other to avoid agitation of the air there was less appearance powders. The three flasks which had been opened were of organisation; and Pasteur concludes that if the flasks therefore taken to the small village of Montanvert, and could be opened and closed in the cellars without the sealed at his lodgings the next morning, after they had disturbance of the air caused by the entrance of the been exposed all night to the dust of the chambers operator, there would be the same absence of vitality in where he slept. Of these three flasks only two prothe flasks filled with air from that locality as if they duced either infusoria or mould. Since the number of were filled with air exposed to a red heat.

flasks altered in this experiment is greater than that in The following results were obtained by Pasteur with those which followed (the twenty flasks previously flasks opened in widely different localities :

noticed), Pasteur concludes that the agitation of the Sixty-three flasks were each one-third filled with a liquid during the journey had no influence upon the clear liquid obtained by filtering water mingled with development of germs. the scum of beer, all solid matter being removed by the It therefore appears to be satisfactorily demonstrated : process of filtering. This liquid is known to be very 1. That the air of inhabited places contains a greater susceptible of change, for exposure to ordinary air for relative number of fruitful germs than the air of unintwo or three days is sufficient to give birth to small habited regions. infusoria or a variety of mucedines. The fluid was 2. That the ordinary air contains only here and there, boiled in all the flasks, and they were hermetically sealed without any continuity, the condition of the first existas in the previous experiments. Twenty of the flasks ence of generations sometimes considered spontaneous. thus prepared were opened and closed in the country far | Here there are germs and there there are none. from any habitation, at the foot of those heights which 3. There are few or many, according to the localities. form the first plateau of the Jura mountains.

Rain diminishes the number; but after a succession of Twenty other flasks were filled with air upon one of fine days they are more numerous. Where the atmothe mountains of the Jura, 850 mètres (2789 feet) above sphere has been for a long time quiet germs are wanting, the level of the sea. Another series of twenty flasks and putrefaction does not take place as in ordinary cirwere carried to Montanvert, near the Mer de Glace, to an cumstances. elevation of 2000 metres (6562 feet), where they were Gay Lussac, Schwann, and Pouchet have performed filled with air and hermetically sealed like the others. various experiments upon liquids in contact with common

Of the twenty flasks opened in the level country, six air, with heated air, with artificial air, and with oxygen developed organic productions. Among the twenty gas, using a mercurial bath to isolate the substances flasks opened upon the plateau of the Jura, only five experimented upon. Some of their results have appeared developed organisms; but of the twenty flasks filled with to favour the theory of spontaneous generation. Pasteur air at Montan vert, when a strong wind was blowing from has ascertained that mercury taken from the bath in any the gorges of the Glacier des Bois, one only produced laboratory is itself loaded with organic germs. He took organisms,

| a globule of mercury, surrounded by an atmosphere of


Analysis of Dublin Milk.


May 3, 1862

calcined air, and passed it into a flask of putrescible | milk from the richer districts is slightly purer than that fluid by the process detailed in the former part of this from the poor districts, yet, when taken singly, the paper. In every experiment of this kind after two days analyses show that the best milk-in fact, perfectly pure an abundant growth of organic products appeared.

milk—was obtained from one of the very poorest The same experiments were repeated with the same districts (Sherriff-street) in the city, and that the rich liquids, with no change of manipulation, with the same district of Rathmines is supplied with as poor a milk kind of mercury, except that the mercury was first as the poor street, Brabazon-street. It will be seen from heated to destoy the germs it contained, and no growths the analyses that three out of the twenty milks examined whatever appeared in the flasks.

were pure, and that the remaining seventeen were more From ail these experiments Pasteur concludes that or less adulterated. powders suspended in the air are the exclusive origin, / According to the published Report of the Lancet the first and necessary condition of life in infusions in Sanitary Commission, out of the twenty-three London putrescible bodies and in liquids capable of undergoing milks examined by them,fermentation. It is easy to collect and observe with the 1st. Twelve were genuine. microscope atmospheric dust, among which may always 2nd. Eleven were adulterated. be found a great number of organised corpuscles which 3rd. That the adulteration consisted in all cases of the experienced naturalist will distinguish as the germs water, the per-centages of which varied from ten to fifty of inferior organisms.

per cent., or one-half the article. [Some infusoria are not more than loath of an inch It will be seen from the mean of the analyses of the in diameter, and if we suppose that the ova of infusoria seventeen adulterated samples of Dublin milk, that the and the spores of minute fungi are no more than one amount of water added is 3'5 per cent. ; in no case did tenth part the linear dimensions of the parent organism, it exceed 5.6 per cent.; so that the Dublin people are there must be an incalculable amount of germs no larger supplied with a much purer article than the inhabitants han zadowoth or todoooth of an inch in diameter. Since, of London; and it may be remarked that the districts according to Sullivant and Wormley, vision with the most selected by the Lancet Commission appear to be all in powerful microscope is limited to objects of about sobooth the better parts of London. of an inch, we need not be surprised if infusoria and The authors described the methods they adopted for other organisms appear in putrescible liquids in far the estination of the different substances, and they pointed greater numbers than the germs in atmospheric dust out that specific gravity of the milk, whether determined visible by the aid of the microscope would lead us to by the instruments called lactometers, or by the still expect. - Tr.]

more accurate plan of the specific gravity bottle, is no Pasteur proposes to continue these investigations, and certain indication of the purity of the milk. expresses the hope that the way may thus be opened Two analyses of the different milks were made. The for a successful investigation of the origin of different following are the means of the two analyses, with the diseases.- American Journal of Science, Vol. xxxii. names of the streets in which the milk was procured. No. 94:

The authors give in their paper also the names of the

vendors of the milks. On the Quality of the Milk Sold in the Poor and other! The investigation was carried out in the laborators of

Districts of Dublin, by WILLIAM J. Woufor and the Museum of Irish Industry, under the direction of SYDNEY R. PONTIFEX, Students in the Laboratory of | Professor Galloway. the Museum of Irish Industry, Dublin.

Rathmines Road. (ABSTRACT.)

Specific gravity . . . . . . . . 1028062 A PAPER on the above subject was read at the meeting

Total amount of organic matter . . . 90275 of the Royal Dublin Society, held on Monday evening,


2.695 April 14. The investigation was undertaken for the


1'591 Albumen

1222 purpose of ascertaining the quality of the milk sold in the poor districts of Dublin; but as the quality of the

Sugar .

3.790 milk can be greatly altered by the kind and quality of

Ash . . . . . .720 the food upon which the cows are fed, samples of milk

Water . . . . 90.005 from the more wealthy districts were analysed in order

- 10C°023 to ascertain whether the poor were worse served than

Cullenswood Avenue. their more affluent neighbours. Twenty samples of milk from as many different dairies / Total amount of organic matter

Specific gravity.

. . . 9*004 were examined; thirteen of the samples were purchased

Butter :

2'217 in very poor districts, and seven were obiained from

Caseine and albumen

2.632 richer districts of the city. The examination proved

Sugar . . . 4:17 that the only adulteration was water.

9'019 The numerous published analyses of milk of known

Ash . .

.655 purity made by various chemists prove that when cows

Water . . . . 90-340 are fed with proper food the quantity of water in the

- 100'014 milk is constant, although the proportions of the various

Duke Lane. substances forming the fixed constituents is variable; Specific

Specific gravity. .

• . . 103237 the normal quantity of water in pure milk is 87.35 per

Total amount of organic matter .

. . 110503 cent. ; this quantity is never exceeded beyond a few tenths

Butter . .

2733 per cent. more or less. The average quantity of water

Caseine and albumen 20756 in the thirteen samples from the poor districts of Dublin,

Sugar . . . 5500

- 10.989 examined by the authors of this paper, was 90'28 per

835 cent., and the average quantity in the better districts

Water . . was 89'4 per cent. Although, taken collectively, the

. .

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May 3, 1862.

Analysis of Dublin Milk.


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Butter :



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North Strand.

Sherriff Street. Specific grayity . . . . . . . 1029:71

Specific gravity : : witter:

. . . . 1029'59 Total amount of organic matter.

. 9•727 | Total amount of organic matter.

matter .


. . . II 692

Caseine. . . 2.48 3.


1'408 Sugar . . . 4'356

Sugar . . 5:419 - 9.629

- 10.607
Ash . . . .


Water . . . . 89.600


Water : : : 87.590 99.899

99'914 Anne Street.

Barrack Street. Specific gravity: . . . . . . 1030*71 | Specific gravity.

• • 1023'05 Total amount of organic matter .

| Total amount of organic matter . .

7.285 Butter 311

Caseine. . . 2491

Sugar . . . 5:30

Sugar . . . 26765

Ash . . . .

Ash . .
Water . .

. . 88:11

. .
Water . . . . . 92.147

998719 Pill Lane.

Charles Street Specific gravity. · 1019-93 Specific gravity. ..

. . . 1023070 Total amount of organic matter . . . . 10:13 Total amount of organic matter. .

7'700 Butter. . . 4'9

Butter, . . 2o365
Caseine. . . 3'967

Caseine . . . 1'985
Sugar . . .

Sugar . . . 3.271
- 10:13

- 7.621 Ash . .

.62 .

Ash . . . .

.600 Water


Water . . . . 91.700 100'00

99.921 Townsend Street.

Ranelagh. Specific gravity . . . . . 1018.58 Specific gravity .

• . 1026.95 Total amount of organic matter. . . 6.453 / Total amount of organic matter .

9:01 Butter . . 2'19

Butter ...

Caseine . .


30601 Sugar . .

. .


2.887 2.400

. . 6.315

Ash .

Ash .
. •625

. .
Water . . . . 92.95

Water . . . . 90-350

99*863 Francis Street

Harrington Street. Specific grayity. .

. 1023:56 Specific gravity . . Total amount of organic matter.


7:552 | Total amount of organic matter .

7:553 Butter .

Butter. . . 2'05

. . 2.890 Caseine.

Caseine. . . 36273

. Sugar . . .

70440 Ash . . . . •610 Water

Water: : : 89.739
acer . .



98.988 Brabazon Street.

Great Britain Street. Specific gravity. ..

Specific gravity:

1026.99 Total amount of organic matter . 9.001 Total amount of organic matter.


Butter .
Butter ·

· · 3135

Sugar . .



2.654 2.991

. . 80954




Water .

. . . 8999

99-466 . N. King Street.

Hanover Quay.

· 1020083 Specific gravity • 8.776 Total amount of organic matter

6.847 Butter


1.6 . •

Caseine. .

Caseine. . 1.887
Sugar . . . 390

Sugar . . .

- 6.645 Ash . . . . *430



. . .




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(OHEMICAL NEWS, 244 On Soil-Analysis.

May 3, 1862. L. Kevin Street.

stores of food in the soil with that vigour which is Specific gravity.

needful in order to appropriate them without hindrance. Total amount of organic matter.


The fact that winter wheat is more delicate and Butter . . . 2486

fastidious in its infancy than most other crops, is perhaps Caseine . . . 1991

the main reason why it does not succeed well on many Sugar . .


good lands, and why it cannot be continuously produced - 8.720

from the same soil, year after year. It is a matter of Ash . .


experience that wheat requires a rather firm seed-bed ; 90745

| beans, oats, and mangold-wurzel approach wheat in

99.990 Bride Street.

their requirements, while barley, peas, and turnips are Specific gravity.

best suited in a light tilth.
. 1023.28

On the other hand, climate, Total amount of organic matter.


weather, and tillage so influence the character of the Butter . . .


soil, that even on light lands wheat may find all the Caseine.


conditions of its growth. The bed which is produced by Sugar . . . 30218

inverting a clover sod, and allowing it to consolidate by 7.813

time and rains, or by passing a heavy roller over it, is Ash .


eminently adapted to wheat, even on a rather light soil. Water Water: : : : 91'456

The fact that in the cases given above from Stoeck

99'892 | hardt, clover succeeded when sown with lucerne or Church Street.

esparsette, would indicate that possibly the condition of Specific gravity. ..



- the seed-bed was the cause of failure. Total amount of organic matter .


These and other facts, which might be adduced to Butter

1'95 Caseine.

almost any extent, indicate sufficiently that chemical

2'013 Sugar . . . 3'402

analysis alone, even if we admit its full nicety and - 7'365

accuracy, can at the best furnish us with a knowledge of Ash · · · ·


but a few of many conditions which must co-operate in Water . . . . 91.875

profitable agricultural production, and, as a consequence, exM 99940 its part in guiding the farmer is but very subordinate.

Taking into the account its evident uncertainty and

clumsiness when applied to estimating the minute On Soil-Analysis, by Professor S. W. JOHNSON, quantities which affect vegetable growth, the part it can of Yale College,

play becomes still more subordinate—we hesitate not to (Concluded from page 227.)

say, insignificant. TWELVE or thirteen years ago, Dr. Anderson, in his! As we write, a fragment from a scientific journal capacity of Chemist to the Highland and Agricultural brings to our notice a discovery which, if real, strengthens Society of Scotland, had occasion to investigate two soils our views in an unexpected manner. It is well known which had become “clover-sick," and he caused them, that iodine is so immensely diluted in sea-water-the soil together with similar adjacent soils which still produced of marine-plants—that none of our tests, though they clover, to be most minutely analysed. Without repro- are among the most delicate, serve to detect it directly, ducing his figures, which may be found in the Trans- and it is doubtful if it has been detected even in the actions of the Highland and Agricultural Society for highly concentrated mother liquors which remain after 1849—51, p. 204, we will merely quote some of the separating the crystallisable salts, yet the fuci find and remarks which accompany the analyses :-“ The results accumulate it, and we must grant that it is present there of these analyses are certainly of an unexpected cha- for them, in sufficient quantity. racter, and appear to me to indicate that, in this instance, Again, Prince Salm Horstmar several years since, in bis the failure of the clover cannot have been dependent admirable researches on the influence of the individual upon the chemical constitution of the soil. In both cases mineral ingredients of plants on the development of oats the results of the analyses of each pair do not present a and barley, found that he could not by any possibility greater difference than would be obtained from the exclude chlorine from his experimental plants. His soils analyses of two portions of soil from different parts of and pots, the salts and water he fed his plants with were any field."

so purified that he could not detect this element in them, In the present year, Stoeckhardt (Chemischer Ackers- and yet he invariably discovered it in the ashes of the mann, No. ii., 1861, p. 85) has published an account of plants. So, too, he found titanic acid in the produce several “clover-sick” soils from Schlanstaedt, which grown on the most carefully purified soils. Now, it is reveal to analysis a greater content of every nutritive mentioned in the CHEMICAL NEWS that he finds a mineral ingredients, both soluble in water and in acids, few hundredths of lithium are indispensable to the than exists in another soil froin Frankenstein which ripening of barley. This element Bunsen has but produces clover and wheat as well. What proves beyond recently shown to be everywhere distributed, yet it has a doubt that the inability of these soils to yield clover been hitherto entirely unnoticed in all soil- and plantdepends upon something besides their chemical constitu- / analyses, because of its occurrence in almost infinitesimal tion, is the fact that lucerne and esparsette still flourish quantity. upon them admirably; and further, clover itself, if sown It must be well borne in mind that Agriculture herself with one of these last mentioned crops, succeeds very -80-called Practice is able of her own resources to well.

judge somewhat of the value of soils, is able to know if A great truth in agriculture is this : Each kind of a soil be fertile or poor, is able to pronounce upon its agricultural plant requires that its seeds be surrounded adaptation to crops, and can to a certain extent decide with certain conditions in order that they may germinate what is a good manure for this or that field. readily and healthfully, so that when the mother coty- We are free to assert that the knowledge which is now ledons are exhausted, the young plants shall attack the to be gathered from experience, is able, in ninety-nine


May 3, 1862. 3

On Sulphur Determinations in Coal, Coke, 8c.


cases out of one hundred, to give a more truthful verdict upon the degree of fertility of the soil. To decide this as to the capacity of a soil, than any amount of analysis, point with some measure of certainty, it is indispensable chemical, mechanical, or otherwise, can do. We would to have recourse to direct observation; it is necessary to give more for the opinion of an old intelligent farmer cultivate a plant in the soil, and ascertain with what than for that of the most skilled chemist in most ques-vigour it developes there : the analysis of the plant aftertions connected with farming. Doubtless the farmer wards intervenes usefully, to indicate the kind and would make some blunders from which chemistry might quantity of the elements that have been assimilated.”save him, but the chemist would be likely to do more " De la Terre Végétale considerée dans ses Effets sur violence to agriculture than the farmer would to la Vegetation," page 283 of “ Agronomie, Chimie chemistry.

| Agricole et Physiologie, Tome premier, 1860.") By these statements, which may, but should not, There has been much progress made in onr knowledge surprise some of our scientific friends, wę merely intend of the soil during the last ten years. This advance has to express an opinion as to the present relative position not consisted in revealing to us the presence of new towards agriculture of those who regard the art from a elements (lithia perhaps excepted), nor in fixing with chemical, and those who see it from an experimental any more certainty the quantitative limits which point of view.

separate barrenness from fertility, it has not shown what If any one has fuller and more inspiring notions of is the composition of a silurian or a sub-carboniferous, a the importance of science in its applications to agriculture drift or a tertiary soil, it has not defined the soil adapted than we have, we desire to sit at his feet and share the to wheat or that productive of clover, it has not indicated higher afflatus. But our inspiration, if it be of the sort the manures which this or that soil needs ; but content that works enduring benefit, must be based on clear ideas with the fact that all soils which naturally support vegeof the directions in which advance is possible, and on a tation contain the elements of vegetation, it has sought full perception of the difficulties that lie before us, and to ascertain in what forms these elements are assimilable, the means of overcoming them.

| how they may be made available, what changes or We have great faith that chemistry and that chemical reactions in the soil affect its productiveness; how feranalysis have done and are to do a work for agriculture, tilisers act indirectly (their influence often having no that shall lay that venerable art under everlasting obli | relation to any supposable direct action), how the soil gations to the youthful science. But not by soil-analysis affects the life of the plant otherwise than by feeding alone or mainly is this to be achieved. We do not it, &c. assert that soil-analysis is worthless, we believe that the We are approaching, in fact, by slow degrees to an probabilities of its uselessness in direct application to understanding of the physiological significance of the practice are so great that we would rarely base any soil, a grand result to which chemistry and physics operations on it alone, and yet it may, in many cases, co-operate. promote science and give us data for conclusions that are | We trust that in future people will not less but more of practical use. But for these purposes it must form appreciate the value of science in its practical and part of a system of observations and trials, must be a especially its agricultural bearings; that here, as in step in some research, must stand not as the index to a Germany, France, and England, the labours of those barren fact, but as the revelator of fruitful ideas.

who seek to unite practice with science may be fostered We hold that soil-analysis long ago played out the and sustained. But to this end scientific men must be part which Dr. Peter would have it perform. In the cautious that in endeavouring to help, however honestly hands of Sprengel it was fertile with new truth, but it and laboriously they may work, they do not hinder. must henceforth be a tool for occasional use, and not an American Journal of Science. engine of discovery. With our advance in knowledge there must be an advance in methods of finding out the On Sulphur Determinations in Coal, Coke, &c., by unknown. Soil-analysis was indeed a means of insight

W. CROSSLEY, Analytical Chemist, Middlesbro'-oninto the secrets of vegetable growth, but it carried with it the measure of its limit. What we call telescopes do In this short article I would draw attention to the fact. not enable us to see the end!

that many analytical chemists, and some of them eminent To study the soil in the hope of benefiting agriculture,

men too, determine the sulphur in coke, &c., by the old we must regard all its relations to the plant. We must

process of boiling in nitric acid. This has frequently examine it not merely from those points of view which

thrown a doubt on the correctness of my analysis. theoretical chemistry suggests, but especially from those

A short time ago, I determined the sulphur in a sample which a knowledge of practical agriculture furnishes.

of coke, and obtained 1:09 per cent. I found afterwards This is becoming more and more the habit of agricul

a sample of the same coke had been sent to a very tural chemists, and the results are of the happiest kind.

eminent chemist, and he only found about 50 per cent. Let us remember what the illustrious Nestor of Agri- | Having done many previous analyses of this same coke. cultural Science, Boussingault, has said as the summing I made inquiry, and found he had adopted this process, up of his protracted experience and study :

The following experiments were done to test the " At an epoch not far distant it was believed that a accuracy of the two processes,—viz., first, fusion with a strict connection existed between the composition and mixture of nitrate of potash, chloride of sodium, and the quality of arable soil. Numerous analyses shortly

carbonate of potash; and secondly, boiling in nitric acid. modified this opinion as too positive. The sagacious To give the nitric acid process every chance, I used a Schübler even sought to prove in a research that has coke containing very little sulphur: become classic, that the fertility of a soil depends more . I fused one gramme of this coke with the following upon its physical properties, its state of aggregation, I mixture in a platinum crucible until all the carbon had power of absorption, &c., than upon its chemical con- / burnt away: stitution."

16 grammes of chloride of sodium "The physical properties, in my opinion, do not enable

nitrate of potash. us, more than the chemical composition, to pronounce

carbonate ?

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