THE PROPOSED NEW MEDICAL ACT. We do not suppose that any of our readers have paid much attention to medical politics. The subject is not an inviting one, nor is the study of it in any sense profitable, and we should owe an apology for introducing it now were it not that the interests of a large section of our readers are likely to be placed in some danger. We mentioned last week that the Medical Council appointed under the Act of 1858 had designs on their business and purses; and we now give such extracts from a Bill the Council hope some day to get introduced to Parliament as relate to Chemists and Druggists, reserving longer comment for a future time.

The preamble of the Act of 1858 was as follows:"Whereas it is expedient that persons requiring Medical aid should be enabled to distinguish qualified from unqualified Practitioners. Be it therefore enacted," &c. The preamble of new Act runs thus:

"Whereas it is expedient that persons requiring Medical aid should be enabled to distinguish qualified from unqualified Practitioners; and whereas it is moreover necessary for the safety and protection of the public towards securing adequately educated Practitioners in the several departments of Medicine, Surgery, and Pharmacy; be it therefore enacted," &c.

For Section XX. of the present Act the Council propose to substitute a Section to the following effect :"It shall be lawful for the General Council to lay down such regulations respecting the education and examination of Practitioners in Medicine, Surgery, and Pharmacy as may appear to them fitted to insure adequate knowledge and skill in the several departments of the Profession; and the said General Council shall then submit said regulations to Her Majesty's most Honourable Privy Council; and the said regulations, if sanctioned by the said Privy Council, shall then be obligatory upon all Universities, Colleges, and other bodies enumerated in Schedule (A) to this Act.' Section XXXI. of the proposed Act stands as follows, and we request our readers to notice the conjunctions italicised:

"Every person registered under this Act shall be entitled, according to his qualification or qualifications, to practise Medicine, or Surgery, or Pharmacy; or Medicine, and Surgery, and Pharmacy, as the case may be," &c.

:

The present Act ends with the following Section :"Nothing in this Act contained shall extend or be construed to extend to prejudice, or in any way to affect, the lawful occupation, trade, or business of Chemists and Druggists.' In the new Act it is intended to

"Omit the words 'Chemists and Druggists.''

An entirely new clause is then added in the new Act, which runs as follows:

"It shall not be lawful for any person to keep open shop for the compounding of Physicians' and Surgeons' prescriptions, unless he be a Licentiate of the Apothecaries' Hall of England or Ireland, or shall have received

a certificate of competency to compound medicine from either of the above bodies, or from the Pharmaceutical Society, or from some other body duly authorised in England, Ireland, or Scotland, by the General Medical Council, to institute the necessary examination, and to grant such certificate, and at such rate of fee as the General Medical Council, with the approval of the Privy, Council, may sanction; and any person keeping open shop for the compounding of medicine, unless qualified as aforesaid, shall, upon a summary conviction for any such offence, before any Justice of the Peace, pay a sum not exceeding 201.; and, for the better protection of the public, and to ensure the carrying out of the provisions as aforesaid, it is hereby enacted that the Medical Council may appoint from time to time one inspector for England, one for Ireland, and one for Scotland, whose duties it shall be to inspect, as often as may be required, all shops where medicines are compounded, and to carry into effect the provisions of this Act in regard to such shops; and that such inspectors be paid such salaries out of the Consolidated Fund as the General Council, with the approval of the Lords Commissioners of Her Majesty's Treasury, may from time to time determine."

On this clause we shall have a good deal to say on a future occasion. We shall now merely point out that with characteristic coolness, the authors of this Bill make no provision for the registration of such Chemists and Druggists actually in business as are not members of the Pharmaceutical Society. It therefore proposes to take away the dispensing business from the bulk of the trade. The Act concludes with a clause to the following effect:

"No patent quack or other medicine shall be sold unless a sworn certificate of its composition be lodged with the Registrar of the General Council, and a copy thereof be open for inspection in the shop or place in which such medicine is sold; and any person or proprietor of a shop selling any secret remedy shall, on summary conviction, for each such offence be liable to a penalty not exceeding 20l."

The above will show what are the designs to which we alluded. We have little fear that the Bill, as it stands, will ever become law; but it may be necessary to take active steps to oppose it, and we recommend such of our readers as are interested to effect at once a hearty combination for the purpose.

SCIENTIFIC AND ANALYTICAL CHEMISTRY.

On Some Curious Properties of Camphor, and its Use in Detecting the Presence of Grease, by JOHN LIGHTFOOT, Chemist at the Broad Oak Print Works, Accrington.

THE detection of minute quantities of grease has hitherto been an unsolved problem, and was much wanted in analytical investigations; this want was more especially felt in an inquiry which came before me concerning the purity or contamination of certain waters

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used for dyeing purposes, and involving great damages in a recent case before a court of law.

Independently of the interests at stake, and the serious nature of this litigation, it was a matter of special scientific interest to discover a qualitative test of sufficient delicacy and unerring precision, to enable us to detect atoms of greasy matters amounting only to fractions of millions.

It was my good fortune to discover such a test at the very time that I needed it most for continuing my investigations, and which enabled me to ascertain the presence of quantities of grease so minute that they escaped other means of analysis.

These researches having yielded, in my hands, results of a useful practical character, I feel it a duty I owe to the scientific public to give an account of them, in my own way, more especially since a very partial and garbled version of a few of the facts which I have discovered have been communicated to a French periodical, viz., the Répertoire de Chimie Appliquée, in their third livraison for the month of March, 1863, by Mr. O'Neil, of Manchester, who has been wanting in candour in not connecting my name with his communication to the correspondent of that monthly record, although he alludes in general terms to the trial which occasioned these researches, and where I was employed as a chemical witness.

The following statements may perhaps prove of use to those interested in the production or purchase of dyed and printed textile fabrics, which form so large a portion of our commercial transactions.

It will hardly be required here to define the meaning and application of the term "grease," for several reasons which will appear in the sequel.

The term may be vague, but it is really the most convenient general epithet to denote a numerous class of substances, including fixed and volatile matters. Thus it will be perceived that spermaceti, although a fatty substance possessing many of the properties of this class, is yet singularly deficient in one of their cha

racteristics.

When small bits of pure camphor, cut and separated from a larger lump with a clean instrument, not permitting the contact of the fingers, are dropped into a glass containing very clean and clear water, they will begin immediately to rotate and move about more or less rapidly, and with strange and erratic energy. This experiment is not new, but it constitutes in itself one of the most interesting and mysterious exhibitions with which we can entertain a social circle.

Being convinced that minute and close observation of natural phenomena always rewards our curiosity and enlarges our perceptions, I carefully studied and repeated this hitherto neglected experiment, and I noticed some additional new and striking features. Thus I found that, if instead of using the torn or cut fragments from jumps of camphor, I detached with a clean needle point one or two of those fine crystals which attach themselves to the cork of the wide mouth phial where camphor is kept, and let them fall on clean water, they at once began to move about with wonderfully increased rapidity, darting away in various directions, as if shot from some minature engine of propulsion, or as if endowed with life and a will of their own; they feared the searching eyes and the magnifying lens of the observer, in their endeavours to find a hiding-place; each crystal quivering and rocking on the water with an apparent high degree

* Steiner v. Pickup. Lancaster and Liverpool Assizes, 1862.

CHEMICAL NEWS, June 27, 1868.

of indignation at their forced contact with the humid medium. This fury gradually diminishes, and a regular dance begins with the various additional particles that may be introduced to the company; they select partners, to some of which they will seem to cling with pertinacity, whilst others will either remain indifferent, or, if attracted, will only stay a very short time in their embrace, detaching and wandering again in search of more congenial floating associates. This sight is pleasing from its variety, interesting from its elegance and the manifestation of an invisible power.

Careful observation demonstrates this power to be a force of reaction, as it is called, such as we see exemplified in the recoil of a gun, or in the flight of a rocket; and, indeed, in all those cases where the removal of a certain resistance at one point of a body under the influence of some internal force or pressure causes that portion of the pressure opposite to the freed point to manifest itself. In the experiment described above, the primary cause of motion is the emanation of a vapour from the volatile camphor; this vapour has a very low tension, the water upon which it floats being capable of dissolving and diffusing this vapour more readily in certain directions of the crystalline axes, thereby removes sufficient vapour-pressure at those points for the opposite side to drive about (by recoil) the nicely suspended particle.

Thus, if we place on the water several well-defined hexagonal plates and prisms of camphor, we will soon notice the mutual attraction of the particles to be stronger in the direction of the radii or angles of the hexagon. This is also accompanied by a decided preference for one of the axes, generally the longest in prismatic crystals; which plainly indicates a polarity in their mode of selfgrouping. In certain positions, two crystals of camphor will attract each other, whilst in other situations there is a mutual repulsion.

It sometimes happens that two crystals of camphor may be thrown on the water, and not have any tendency to locomotion; when this is the case, a continual trembling or vibration may be noticed to possess the crystal. Now, it may be observed, that, whenever two such stationary vibrating crystals come in contact by attraction, immediately an eccentric irregular change of place takes place, as if the force agitating each, previous to the grouping, acted, at first, in a downward direction (which we have every reason to conclude is actually the case), and, the two combined down currents associated with the deviation from the horizontal vibration, produced a new resultant force, inclined from the perpendicular. Thus accounting satisfactorily, on mechanical principles, for the assumption of fresh paths, from two comparatively quiescent particles.

It also happens that the rotation of two independent crystals may be reversed, by grouping with one another, and again modified by a third adjunct, and so on for many other combinations of particles.

(To be continued.)

TECHNICAL CHEMISTRY.

The Chemistry of Agriculture.

(Continued from page 294.)

THE experiments carried on during the last twenty years by Mr. Lawes and Dr. Gilbert, have led to results to the theoretical views of Baron Liebig, and the general that are, in many important particulars, directly opposed tendency of those results is to give the chemistry of

agriculture an aspect widely different from that indicated by Baron Liebig's theory, either in its present or previous phases. The main point of difference, in regard to practical agriculture, consists in the views entertained as to which of the constituents of plant food are, under ordinary circumstances, most liable to become deficient, and which of them, consequently, require to be supplied from extraneous sources as artificial manure, or to be accumulated for the growth of particular crops, by systematic rotation, by fallow, and by feeding cattle to produce

manure.

According to Baron Liebig's theory of plant nutrition, the main substance of plants-consisting of carbon, hydrogen, oxygen, and nitrogen-is regarded as originating from carbonic acid, water, and ammonia, furnished by the atmosphere, but the growth and full development of plants by the assimilation of these food materials is held to be dependent upon the presence of "certain mineral substances which are indestructible by fire, and remain as ashes after the incineration of plants." According to this theory, in its application to agricultural practice, the fertility of land depends upon the presence in it, of the mineral constituents of the plants to be grown; the degree of fertility being held to be proportionate to the amount of those mineral constituents in the land, while the maintenance or increase of its fertility is held to depend on the restoration of the mineral constituents removed by crops or the increase of their amount in the land.

The influence of manure was ascribed to the mineral substances it contained, and which originated from the plants consumed as animal food; but since the export of produce from land was attended with a permanent abstraction of mineral constituents, it was considered that, in this way, land gradually became impoverished, and that it would eventually become incapable of yielding

crops.

One of the first fruits of the practical application of this theory was the invention* of artificial, manures to be applied for the purpose of preventing land from being thus impoverished, and also of augmenting its fertility, by giving it a greater power of determining the assimilation of atmospheric food by plants. The preparation of these manures was to be regulated according to the composition of the ashes of the plants to be grown, and the quantity applied to land was to be regulated by the quantity of ash constituents removed from it by the previous crop. The virtues of these patent manures, and the principles on which their manufacture was based, were fully expounded in a pamphlett published in England, but the results obtained by their application were not satisfactory. This first attempt to apply the theory to agriculture was a decided failure. The ash theory of manures, derived chiefly from the consideration of the circumstances of plant nutrition in a natural state, was found to be insufficient to explain the ordinary routine of agriculture, in which the conditions of plant nutrition are essentially artificial. Analogy, that able but deceptive guide, failed to furnish a true theory of agriculture, by the application to it of abstract scientific principles.

The experimental investigation of this subject by Mr. Lawes and Dr. Gilbert, was commenced with a recognition of the artificial nature of agriculture. Its object

* Specification, 10,616. October 4, 1845.

"An Address to the Agriculturists of Great Britain, explaining the principles and use of his Artificial Manures." By Professor Justus Liebig. Liverpool, 1845.

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was to obtain data that would serve as evidence explanatory of the established routine of agriculture. The action of manures was one of the first questions studied. Having observed that, by growing wheat continuously on the same land without manure, the crop was proportionate to the climatic conditions of the year, that it was largest in the year when the atmospheric influence was greatest, but was in no case a full crop, it was endeavoured to ascertain whether the deficiency was due to a want of available minerals in the soil, or to the want of a sufficient supply of ammonia. Wheat was grown on several plots of land, manured with different mixtures of mineral manures; one plot was left unmanured, another plot was manured with the ashes of farmyard dung, and another with an equivalent quantity of farmyard dung. In all the plots where mineral manures alone were employed, the crop was little more than that on the unmanured land, while on the plot manured with farmyard dung it was nearly half as much more than on that of the plot manured with only the ashes of farmyard dung, which was just the same as that on the unmanured land. In other plots of the same land, manured with minerals and ammoniacal salts, the crop was as large as on the plot manured with farmyard dung. Liebig's wheat manure alone, gave a crop but little larger than the unmanured land, while a plot manured with Liebig's wheat manure and ammonia, gave a crop nearly half as much more than that of the plot manured with Liebig's wheat manure alone. It was evident from these results that, whatever the amount of ash constituents in the soil, or supplied to it by manure, they are not effective in augmenting the crop, unless ammonia be supplied at the same time. They show that the supply of ammonia from the atmosphere is not sufficient to produce a full crop, and that the mineral constituents were rendered available and effective in producing a larger crop only in those plots where ammonia was supplied as manure, either in farmyard dung or otherwise.

It is not surprising, therefore, that Mr. Pusey should have regarded these important results as completely establishing the opinion he had already expressed as to the entire failure of the mineral theory as a guide to the use of manures in practical farming. Nor is it any more surprising that Mr. Lawes and Dr. Gilbert should have deduced from these results the conclusion that, in practical agriculture, the supply of ammonia is especially important, since the produce is more in proportion to the supply of ammonia than to the supply of ash constituents, and since the ash constituents, however abundant in land, are not effective unless there is also abundance of available nitrogen in the soil-a conclusion directly opposed to Baron Liebig's mineral theory, according to which the crop is held to be directly proportionate to the ash constituents in the soil.

But Baron Liebig ridicules these results, and declares the experiments to be absurd. He maintains that the increased crop obtained by applying ammonia to a plot of land-that had the previous year been manured with superphosphate of lime and potash, and yielded then only the natural produce of unmanured land-proves nothing, and he ignores the fact that while the application of mineral manures on this plot, did not produce any effect beyond that on the unmanured land-the application of ammonia in the following year at once had the result of rendering those minerals effective, and of increasing the crop. He endeavours to make it appear that Mr. Lawes and Dr. Gilbert regard ammonia as being alone sufficient to produce wheat crops, and that

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they intend the application of ammonia-as carried out in their experiments, made for the purpose of investigationto be adopted in agricultural practice exactly as in those experiments, and he then enters into a calculation to show that the quantity of ammonia obtainable in all Europe would be insufficient to supply a pound an acre to the land under cultivation. In this way he endeavours to prove that his theory is in no way affected by the results obtained by Mr. Lawes and Dr. Gilbert, that it is even more firmly established than ever.

Eut it has been most expressly pointed out by Mr. Lawes and Dr. Gilbert that they do not maintain that the mineral constituents can be dispensed with, but simply that, in the ordinary course of agriculture, they are abundant in relation to other constituents, and that, to obtain a full crop of corn, a liberal supply of available nitrogen must be provided, and that, notwithstanding the abundance of mineral constituents, they will not be effective without it. Baron Liebig's assumption that it is intended that this supply of available nitrogen should be effected by the direct application of ammonia is entirely gratuitous, and is quite inconsistent with the description given by Mr. Lawes and Dr. Gilbert of the means by which this supply is to be ensured. They say that besides being expensive, ammonia cannot be procured in the market in any large quantities, but by cultivating turnips and the leguminous plants, and by feeding cattle with these crops, and with imported food, a large amount of ammonia is accumulated upon the farm, for the growth of corn crops, which more especially require it; and that in this sense, rotation of crops may be considered as an economical means of obtaining ammonia. In spite of this, Baron Liebig describes the difference between his opinion and that of Mr. Lawes and Dr. Gilbert, as to the importance of ammonia, to consist in their recommending the purchase of ammonia as the only means of increasing the produce of corn, while his theory teaches how to attain that end without purchasing ammonia. He comments at great length upon the fact pointed out by Mr. Lawes and Dr. Gilbert, that the nitrogen obtained in the corn crop, is in no case as much as the nitrogen supplied to the soil as manure, and without attempting now, to question this fact, he argues that it is a proof that their opinion of the importance of ammonia for the growth of corn can only be the result of prejudice, or of an interest in the sale of ammonia salts.

With wonderful boldness, and in total disregard of the enormous consumption of guano, Baron Liebig declares that ammonia salts are not used by any farmers in any country, still repeating his assertion that the results of Mr. Lawes' and Dr. Gilbert's experiments fully confirm his theory, and declaring that it is impossible to say he is in error. He says, with admirable naiveté, that they should have followed his course, in order to have thought as he thinks, and to have come to the conclusions he has come to; but, though this is possibly true, it is not the less a fortunate circumstance that they have, as Baron Liebig says, followed their own course without heeding his theory, and although he considers they have consequently involved the clearest facts in an inextricable embroglio of misunderstanding, rendering them obscure and unintelligible, the real interests of agriculture are not likely to suffer from the knowledge of such facts as the Rothamsted experiments have established, however fatal they may be to theories.

The Rothamsted experiments prove that the mineral theory of manures, like so many other brilliant theories of Baron Liebig's, will not bear the test of practical

CHEMICAL NEWS, June 27, 1863.

application. Like the theories of animal nutrition, of fermentation and decay, its deficiencies have been hidden only by its attractive form, and the effective plausibility of its author's mode of exposition. The mutations that theory has undergone, since its first promulgation in 1840, are in themselves sufficient proof that, as a theory of agriculture, it was a premature growth, while a science of agriculture was wanting. It is but lately that materials have been accumulated for such a science, and they have been chiefly furnished by the experimental results of Boussingault, Lawes, and Gilbert. The attempt made by Baron Liebig to save his theory by maintaining that he included ammonia salts among the "mineral" constituents of land, and that the sources of nitrogen in plants, were comprised among the mineral constituents of plants-to be ascertained by analysis of their ashes, and supplied as manure-is a position so startling and inconceivable, that it is difficult to find words to describe its total inconsistency with truth. It must be remembered also, that there is a wide difference between what Baron Liebig now calls his "mineral theory," namely, the theory that all plant food consists of inorganic substances, and the application which he made of that theory to agricultural practice. It is not in consequence of misunderstanding the application of his theory, that Baron Liebig is represented as having held that the fertility of land is in direct proportion to the amount of the mineral constituents of the ash of plants to be grown upon it, and that the true practice of manuring was to supply those constituents only, leaving the atmosphere to supply ammonia. This is no misunderstanding or misinterpretation of Mr. Pusey's or of Mr. Lawes' and Dr. Gilbert's, but the distinct expression of the application of his theory as given by himself in the " Chemistry Applied to Agriculture;" in the "Address to Farmers,” and in the specification of his patent. In every illustration he gives of that application, it is potash, phosphoric acid, lime, silica, of which he speaks as being permanently abstracted from the soil, and requiring to be replaced by manure.

The influence of manure was uniformly ascribed to its ash constituents; the practice of rotation was explained on the assumption that the alternate crops required, in one case, potash, in another, lime, in another, silica; the benefit of fallow was ascribed to the disintegration of alkaline minerals in the soil; in no case was ammonia or nitrogen-yielding manure mentioned, except in direct antithesis to the mineral or ash constituents of manure. In no case is the importance of available nitrogen in the soil, as the essential condition of the efficacy of the mineral constituents of plant ashes, mentioned. In no case is it shown that rotation or fallow are means of providing a supply of available nitrogen for the growth of corn. This is the case not only in the earlier editions, but also in the later publications of Baron Liebig on this subject. Nitrogen is every where spoken of as one among the atmospheric materials of plant food which, like carbonic acid, was supplied from that source, in amount sufficient for all purposes of agriculture, and without the necessity for any special provisions for its being supplied in greater proportion to particular crops. It was even pointed out, as "of great importance for agriculture, to know with certainty that the supply of ammonia is unnecessary for most of our cultivated plants, and that it may be even superfluous, if the soil contains a sufficient supply of the mineral food of plants, when the ammonia required for their development will be furnished by the

See CHEMICAL NEWS, ante, p. 258.