I Chemical Researches on_Hydraulic Cements, by M. E. FREMY. THE admirable studies of Vicat on hydraulic cements have placed beyond doubt the fundamental fact that the hydraulicity of a cement is owing to the compound which is formed when limestone is calcined with clay. formed, and to which is the hydraulicity of cements In the reaction of lime upon clay what bodies are attributable? It must be remembered that this theoretical question is not yet completely solved, and that this uncertainty constitutes perhaps one of the causes of the difficulties which sometimes occur in the manufacture and employment of hydraulic cements. of hydraulic cements. The formation of a silicate gela- and the ligneous fibre is left as a soft and pliable material of a brown colour. After washing with abundance of water the fibre is worked up into paper in a manner similar to that followed in the case of rags, only a little more bleaching powder is required. The fibre, however, is rather short in nature, and hence paper entirely made of it is extremely liable to tear. It is customary, therefore, to give strength to the paper by mixing the pulp from the esparto fibre with the pulp from the rags, and a common proportion is equal parts of the esparto and rag pulps. The paper manufactured from the Spanish grass, and more or less rags, is largely employed as a printing paper, and the majority of the Scotch newspapers are now printed on the mixed fibre and rag paper. In order to understand the causes which affect the The liquid obtained from the boilers where the original esparto fibre is acted upon by caustic soda is a dark solidity or the decomposition of hydraulic cements their brown coloured liquid, which still retains one-third of true constitution must first be known. This important its original soda as caustic. Attempts which have been point I have principally considered in the following inmade to employ this liquid over again, with the addition vestigation. of more soda, have shown the impracticability of getting admits the formation of a double silicate of alumina and In the calcination of an argillaceous limestone, Vicat the whole of the soda to act. Indeed, in using the pro-lime, which, by becoming hydrated, causes the setting portions stated previously-viz., 14 lbs. of caustic soda to the cwt. of fibre, or in a boiler 14 cwt. of soda to the 12 cwt. of fibre, only 1 cwt. of soda is taken up and neutralised, and the remaining cwt. is left as caustic. Trials which have been made to use only the 1 cwt. of soda in the boilers have not been successful. The spent soda liquor necessarily contains much organic matter in solution, and being of a caustic nature, it possesses properties which render it pernicious and destructive to fish when it is run directly into a fishing stream. Even when diluted with water to the extent of many times its own volume, the liquid possesses the power of killing fish within a few hours. The large quantity of water required in paper manufactories necessitates that they be placed on the banks of streams; and whilst the destruction of trout may be a matter of little moment, yet the discharge of much spent soda liquor into a salmon stream is of much individual and national importance, tending as it does to foul the water and diminish the proportion of oxygen gas dissolved therein, besides conferring more or less caustic properties upon the water. Several instances have occurred in Scotland of the destruction of salmon and salmon fry in this manner, and even where direct poisoning might not be traced, yet it is undoubted that such discharges and the consequent fouling of the stream must tend to deteriorate the health of the fish, diminish their growth, or probably drive the fish from the stream. Two plans have been suggested and put in operation for the arrestment more or less completely of the soda liquor. The first method is the boiling down of the ley, heating the residue with carbonaceous matter, such as fine coal or sawdust, and the recovery of the soda from the calcined mass; and the second process is the reception of the liquor in large open tanks or cesspools, where the liquor may percolate through a sandy and gravelly soil. Both plans have been carried into practice, and have been successful. These are some of the principal points connected with the employment of esparto fibre or Spanish grass as a substitute for rags in the manufacture of paper, and as the fibre is obtained comparatively cheap and yields one half of its weight of paper, the manufacturers regard this grass as a great boon. Royal Polytechnic Institution.-The evening chemistry class conducted by Professor Pepper and Mr. T. Coles, in connection with the Science and Art Department, will commence on Oct er 17 at 8 p.m. Al3CaO,6HO SiOs,3CaO,6HO, which produce the setting of the cement. According to these two theories, the hydraulicity of the cements is owing to a simple phenomenon of hydration which induces the setting of the plaster. The result of my researches serves to show that the setting of hydraulic cements in water is attributable to two different chemical actions,-1. The hydration of aluminates of lime; 2. An action in which the hydrate of lime combines with the silicates. According to one theory the calcareous aluminates and silicates found in the cements exert different influences at the moment of the setting; the former became hydrated, the latter combine with the hydrate of lime. This theory of the hydraulicity of cements is founded 2. Silicate of alumina and of lime. With these bodies several series of experiments were undertaken, the principal results of which I will now give. Silicates of Lime.-I prepared silicates of lime synthetically by every possible method both in the wet way and the dry way. For this object I had recourse to the double decomposition of a soluble silicate by a salt of lime, to the reaction of hydrated silica upon lime, to the calcination at different temperatures of various mixtures of silica and lime. I thus obtained precipitated, fritted, and fused silicates of lime. These salts, reduced to an impalpable powder and mixed with water, produced pastes which slowly dried without presenting the phenomenon of setting. I think, then, I am warranted in saying that if silicate of lime is formed in the calcination of an argillaceous limestone, the setting of the cement cannot be attributed to the hydration of this salt. Double Silicates of Alumina and of Lime.—In this series of trials, which, like the preceding, represents many experiments, I combined silica by the dry way in all proportions, not merely with alumina and lime, but to the alumino-calcareous silicates of alkalies, and added magnesia and oxide of iron. The contact of these multiple silicates with water produced the same result as that of silicates of lime with water. They never produced a setting to be compared with that which characterises hydraulic cements. The hydration of the double silicate of alumina and lime which may be formed in the calcination of an argillaceous limestone is not, then, the cause of the solidification of the water in hydraulic cements. Aluminates of Lime.—I have carefully studied the properties of aluminates of lime, the importance of which in the setting of cements has been shown, and for the first time, by MM. Rivot and Chatonay. I have produced aluminates of lime by calcining mixtures of alumina and lime in various proportions and at different temperatures. To avoid sources of error arising from the presence of foreign matters, the alumina employed in my experiments was pure, and produced by calcination from ammonia alum. The lime, produced by calcination of Iceland spar, was equally pure. The lime produced from Iceland spar by calcination in a blast furnace forms a crystalline mass, which breaks like marble. As these experiments often require the highest temperature producible by a blast furnace, and ordinary crucibles cannot resist the influence of the lime under these circumstances, I employed with great advantage black-lead crucibles in the preparation of aluminates of lime. Their only inconvenience is, they allow the sulphurous vapours of the combustible to pass, which produce traces of crystallised sulphide of calcium on the surface of the aluminates. In this calcination the influence of the sulphur may be avoided by using a double crucible of carbon and by placing powdered lime between the two walls of the crucibles. In this study of aluminates of lime, I first observed a very curious fact-namely, that alumina is an excellent flux for lime, which even acts upon this base more strongly than silica. Operating with various proportions of lime and alumina, I obtained perfectly fused aluminates of lime by heating in the blow-pipe furnace mixtures of The calcareous aluminates, containing the largest quantity of lime, are crystallised; they have a saccharoidal fracture; their reaction is strongly alkaline; they combine with water with disengagement of heat; they may almost be compared to quick-lime. Although the following consideration diverges from the subject in question, I cannot help calling the attention of metallurgists to the fusibility and the alkalinity of aluminates containing excess of lime. Similar compounds absorb and strongly retain sulphur and phosphorus; their presence in the slags of furnaces does then, in some cases, eliminate from the castings the sulphur and phosphorus which are so justly feared in the preparation of iron for making steels. These very basic aluminiates of lime, which behave in water like quicklime, play no part in the setting of hydraulic cements. But the same cannot be said of the aluminates of lime represented by the formulæ— Al2O3, CaO,Al2O3, 2CaO, A12O3,3 CaO, and which are less basic than the preceding. These aluminates, when reduced to a fine powder and moistened with a small quantity of water, solidify almost instanable hardness in water. taneously, and produce hydrates which acquire consider The aluminates of lime which set in water have also the property of agglomerating inert substances, like quartz. I mixed aluminate of lime-Al2O3,2 CaO with 50, 60, 80 per cent. of sand, and obtained powders which when mixed with water acquired the hardness and solidity of the best stones. point of view presented by these mixtures of aluminate It is easy to understand the interest in a practical of lime and silicious substances, when it concerns the production of blocks capable of resisting the influence of atmospheric agents and sea water; the explanation of the durability of sea-proof constructions is probably the employment of blocks which are formed almost entirely of silicious substances, bound together by a small proportion of aluminate of lime. My researches on aluminates have enabled me to explain one of the most interesting peculiarities in the manufacture of Portland cements. These highly esteemed cements are not, we know, of good quality unless produced aluminates of lime, which by reason of their composition at a very high temperature. Now I have found that solidify in water, do not acquire this property to any great extent unless exposed to an intense heat. This curious fact I proved by heating the same mixtures of alumina and lime at different temperatures; that which was highly calcined in the wind furnace, and which had fused, was much more hydraulic than that which had been heated to a lower degree. Thus, in the manufacture of Portland cements, the calcination makes the lime react upon the alumina at a high temperature, and determines the fusion of the calcareous aluminate, which then assumes its maximum of hydraulicity. The result, then, of the different experiments I have analysed is, that aluminate of lime is the principal hydraulic agent in cements which set rapidly. Is this calcareous compound the sole agent in the hydraulicity of cements? This important question remains to be examined. (To be continued.) PHARMACY, TOXICOLOGY, &c. Can Methylic Alcohol or any Derivative of it be readily Detected in Chloroform, Ether, Sweet Spirit of Nitre, and Sal Volatile ?* by Mr. JOHN TUCK. IT will, I think, be plain to all, that the detection of methylated spirit, under the varied forms of chloroform, ether, sweet nitre, and sal volatile, is a very different subject to its simple detection when not in any way its preservative effects, as in the various tinctures of the chemically altered, and used merely as a solvent or from Pharmacopoeia. In the former case we have to deal with the spirit after it has undergone some complex • Read at the Pharmaceutical Conference. the tests. changes, or been mixed with various other bodies not removeable by mere distillation, whilst in the latter we have only the plain unaltered spirit, which, although it may be contaminated with organic matter, can, nevertheless, be separated from it by simple distillation. In the case of chloroform and ether, we have to deal not with methylic or ethylic alcohols at all, but some derivatives of them; in sweet spirit of nitre and sal volatile, we have to deal with the spirit holding in solution various other bodies, solid, liquid, and gaseous; and our aim here is to remove or decompose them, so that they shall not in any way interfere with the application of Chloroform, as is well known, can be prepared from wood naphtha, acetone, chloral, the acetates of lime, soda, and potash, oil of turpentine, and other essential oils, as well as from ethylic alcohol and methylated spirit. It is, however, generally prepared from ethylie alcohol and methylated spirit, because the resulting product is much purer and the yield greater than when derived from any other source, Chloroform obtained from crude wood naphtha has an empyreumatic odour very difficult of removal, but I expect this entirely results from the oily empyreumatic bodies previously existing in the naphtha. The patent naphtha would undoubtedly yield as fine a sample as any derived from pure alcohol; I am not aware, however, of any having been made from this source. Although chloroform, like alcohol and oxalic acid, may be derived from many sources, yet, when freed from all impurities, it is of a certain, definite composition. It is said to have been known in former times, but this is very doubtful; we, however, know for certain that Dumas first pointed out its true chemical composition in 1834, and considered it to be the ter- or perchloride of the compound radical formy! CHCl3. The two elements constituting the compound radical formy! exist in many organic bodies, and in the two principal sources of chloroform are as follows:: C4H6O2 C2HO2 Ethylic alcohol, or spirit of wine Methylic alcohol, or wood naphtha. and when these are distilled with chloride of lime (chlorinated lime) and slaked lime, some complicated decompositions ensue, and chloroform is produced. It being clear that there can be no chemical difference in pure chloroform, from whatever source derived, and that it is formed as readily from methylic as ethylic alcohol, it is, therefore, useless to expect any chemical test for distinguishing it, when made, from methylated spirit and properly purified. In the preparation of chloroform from wood naphtha, an oily body, lighter than water and containing chlorine, is formed. An oil is also formed in its preparation from alcohol, but it differs from the oil obtained in making it from wood spirit in being heavier than water, and in having a lower boiling-point; the crude methylated chloroform will therefore be contaminated (admitting it to be equally produced from both spirits) for a tenth part of its bulk, with a greater amount of a light oil proportionate to the greater amount yielded by wood naphtha, and it will be evident that the chloroform, if not thoroughly purified, will be of a somewhat lighter gravity than that prepared from pure alcohol,- so that, to sum up all the essential points, good chloroform, from whatever source derived, is a limpid colourless liquid, with a fragrant ethereal odour and a sweetish taste. It is entirely free from alcohol, ether, empyreumatic oils, chlorine, chloral, or any acid reaction with litmus paper. When evaporated from the palm of the hand, or better from several thicknesses of blotting-paper, it does not leave behind any strong disagreeable smell. Dropped into water it falls to the bottom, and remains perfectly bright; it has a specific gravity of about 1'496 to 1.500, and evolves no gas, or but a bubble or two, when potassium is dropped into it. It is not coloured by agitation with sulphuric acid, and is soluble in alcohol and ether in all proportions. As the results of many experiments, I can find no difference in the behaviour of the two chloroforms respectively prepared from methylated spirit and from pure alcohol. I should state that I took every precaution to have perfectly reliable specimens of the two chloroforms as standards of comparison, and that Messrs. Duncan and Flockhart kindly assisted me in this inquiry by placing some fine specimens of the chloroforms at my service. I should also state that this eminent firm have told me that they know of no test for distinguishing the pure from the methylated chloroform. Methylated ether is, I believe, prepared commercially in the same way as that from the pure alcohol: it must therefore be looked upon as being, under ordinary circumstances, a mixture of nearly 10 per cent. of methyl ether (probably contaminated with a small portion of sulphate of methyl) with ethyl ether. Now the problem really to be worked out is the following:-Can a mixture of 10 per cent. of methyl ether be selected in 90 per cent. of ethyl ether? These two ethers differ very much in their general properties and behaviour with other bodies; although both are oxides of their respective radicals, they, so unlike their hydrated oxides or alcohols, have no properties in common. The The oxide of ethyl, or ether, as is well known, is a very volatile, fragrant, colourless, transparent liquid, neither acid nor alkaline, and very combustible. Its specific gravity varies greatly with the temperature and the amount of spirit mixed with it; the ether of the British Pharmacopoeia has a sp. gr. 735, and is said to contain about 8 per cent. by volume of alcohol, and to boil below 105°. Absolute ether is said to have a gravity, at a temperature of 60°, of about 720, and causes intense cold by its volatilisation. oxide of methyl, on the contrary, is a permanent colourless gas, very soluble in water, and still more so in alcohol, wood spirit, and ether. After submitting the mixed ethers to many experiments, I have to report that I know of no other test for distinguishing the methylated from the pure alcohol ether, other than the boiling-point, first pointed out, I believe, by Macfarlane. I find, with him, that the methylated ether has a much lower boiling-point than the pure alcohol ether, the difference ranging in my experiments from 14 to 17° of Fahrenheit. I found, on boiling methylated ether with sulphuric acid (sp. gr. 1848), that it became of a decided brown colour, whilst pure alcohol ether, under the same treatment, remained quite or very nearly colourless. The existence of methylic alcohol in sweet spirit of nitre is easily proved; without any preliminary treatment whatever, the iodo-hydrargyride of potassium clearly indicates it. The plan I adopt previous to applying the oxidation method of testing, is to mix the sweet nitre with an equal bulk of a solution of caustic potash (twice the strength of the Pharmacopoeia solution), and, after allowing the mixed liquids to stand about an hour, I distil off an amount of spirit equal to the original sweet nitre, and then oxidise, as in the case of a spirit distilled from a tincture. I found, on distilling some samples of sweet nitre mixed with the solution of potash, that they boiled with explosive violence, giving off | nistration. One object to which particular attention will sudden jets of vapour. This, however, can be easily prevented by the well-known method of placing some portions of wire in the retort; for this purpose iron wire will do. The method I adopt in testing sal volatile for methylic alcohol is to first dilute it with an equal amount of water, then neutralise the ammonia with dilute sulphuric acid, and distil carefully over an amount about equal to the original spirit. I then test a portion of the distillate with the iodo-hydrargyrides of potassium; and if a further test is desirable, I apply the oxidation method of testing to another portion. In conclusion, to sum up the results of this paper in a few words: Chloroform can be, and is, prepared from methylated spirit as good as, and the same in chemical composition as, that from pure alcohol; consequently, there can be no test to distinguish between them, there being no difference in them. Methylated ether can principally be detected by its boiling point. And the presence of methylic alcohol in sweet nitre and sal volatile can be thoroughly proved by both the icdo-hydrargyride of potassium test and the oxidation method of testing. Wilton, near Salisbury, August, 1865. PROCEEDINGS OF SOCIETIES. BRITISH PHARMACEUTICAL CONFERENCE. Birmingham Meeting. THE meeting at Birmingham was in every respect a highlysuccessful one. The report stated that the number of members has more than doubled during the year, and, as will be seen, a number of valuable communications were read to the meeting. The President, Mr. Deane, opened the proceedings with an excellent address, which we regret not to be able to print at length. After congratulating the members on the success of the Conference, he spoke of the publication of the British Pharmacopœia, and justified the Medical Council in the publication of bare formula, without notes and comments. He then spoke of the revised edition now in preparation, and as the speaker has probably good sources of information, we quote this paragraph of the address at length : "As you are aware, the Pharmacopoeia is at present under revision by a Committee whose names are a sufficient guarantee that the work will be performed in a manner satisfactory alike to the prescriber, the pharmaceutist, and the purely scientific man; and I anticipate that the new edition will show that the existing volume contains the nucleus of the best medical code which we have yet seen. Probably it will be found that the chemical notation and some other matters of abstract science which vary with the changing opinions of scientific men will be entirely omitted. That physicians will have greater liberty in the use of the old and convenient apothecaries' symbols for grains, scruples, and drachms, and that with the general revision of the work and the removal of many existing inconsistencies, we shall have the insertion of formula for a large number of generally prescribed remedies for which it is most important there should be recognised galenical preparations." The preparation of an Indian Pharmacopoeia was then alluded to, and its scope described as follows: "Its object and aim is to supply medical men and pharmaceutists in India, as well as the medical students whose education may be conducted in the Government colleges, with a mass of information respecting the more useful drugs, including their method of preparation and admi- | be given is the introduction into notice of the more important drugs of India, hitherto but little employed except by native practitioners. As it will be necessary in most cases to describe the physical characters of the drugs, to point out their place of growth and manner of preparation, Pharmacopoeia of India will have somewhat the character as well as to notice their therapeutical applications, the of a dispensatory. It is not intended to introduce into it chemical processes; and certain other drugs and preparations specified in the British Pharmacopoeia will probably be omitted from that of India, as being either superfluous or not adapted to a hot climate such as that of India. It is intended that the work shall contain lists of drugs in some of the principal Indian languages, in order to facilitate the identification of drugs met with for sale in the bazaars." Mr. DEANE next spoke of accidental poisonings, the social position of chemists and druggists, the evil consequences of unnecessary competition in trade, and the necessary interference of the Excise with the sale of articles compounded with methylated spirit. At the conclusion of the address a vote of thanks to the President was proposed, and carried by acclamation, ACADEMY OF SCIENCES. September 18. M. PAYEN Communicated a memoir " On Iodide of Potassium." The author has remarked that this important medicine is rarely found in a state of purity. It is usually alkaline, and nearly always contains an excess of iodine. He has also made the curious observation that saturated solutions of iodide, and also of bromide of potassium, unlike the alkaline chlorides, act in the cold on starch granules, which, under the influence of the solutions, acquire twenty or thirty times their natural size, so that the liquid becomes a colourless, transparent mass. The commercial iodide, he states, is easily purified by saturating the potash with hydriodic acid, and by separating the excess of iodine by sulphuretted hydrogen, boiling, rest, and filtration. A solution of a salt so purified, it is said, remains colourless in a stoppered bottle after exposure to both diffuse and direct sunlight. In a slightly alkaline solution of the iodide, carbonic acid sets some iodine at liberty: atmospheric air produces the same effect, no doubt because of the carbonic acid present. With regard to the curious phenomena of the alternate colouration and decolouration of iodide of starch by heat and cooling, the author believes he has demonstrated that the decolouration by heat is occasioned by the dispersion of the amylaceous particles, the colour returning when the groups of particles contract on cooling. In conclusion, M. Payen dwelt on the neces sity of using the pure iodide in medicine, and pointed out that the reaction on starch described above suggested a new inquiry into the physiological effects of the salts. After the memoir was read, M. Chevreul made some remarks to the same effect. Apropos to a Ministerial order, that only utensils tinned with pure tin should be used in the military hospitals, M. Jeannel gives "A Process for Detecting Small Quantities of Lead in Tin." He treats five decigrammes of the metal filed off with an excess of nitric acid diluted with three times its weight of water, boils the mixture, filters, and then drops into the solution a crystal of iodide of potassium. If only one ten-thousandth of lead is present, a yellow precipitate is formed, which does not disappear on adding an excess of ammonia. M. Gaudin presented A Representation in Relief of the Molecule of Chlorosulphate of Strychnia "—a compound of two molecules of strychnia, four molecules of sulphuric acid, four atoms of chlorine, and sixteen molecules of water. No description could give our readers any idea of this figure, and we pass it, though with reluctance, since it offers a curious study. M. P. Schutzenberger presented a note "On the Action of Acetic Anhydride on Cellulose, Starch, Sugars, Mannite and its Congeners, the Glucosides, and certain Vegetable Colouring Matters." The note makes known some important facts. M. Berthelot has shown that sugars and their congeners function like polyatomic alcohols, and are capable of forming true compound ethers. He obtained these ethers by treating the sugars, &c., with a hydrated acid; but the process is tedious, and yields very small quantities of the ethers. In the case of the acetic ethers derived from sugars, &c., M. Schutzenberger has obtained much better results by using acetic anhydride. The etherification is completed in a few minutes, and, in general, does not require a higher temperature than the boiling-point of the anhydride. The only products of the reaction are hydrated acetic acid and an acetic derivative soluble in the hydrated acid, but soluble or insoluble in water, according to the nature of the substance experimented upon. In the latter case, the derivative is separated on diluting the thick syrupy liquid formed when the reaction is completed; in the former case, the syrup is diluted, decolourised, if necessary, by animal charcoal, and evaporated to dryness under the air-pump. The author at present gives only a very short account of the compounds he has obtained with starch, cellulose, cane sugar, glucose, &c., but this we are obliged to defer until next week. M. Schutzenberger also communicated a note "On a New and Easy Means of Preparing Gaseous Methyl or Methylide of Methyl." When acetic anhydride is heated with an excess of peroxide of barium, a large quantity of gas is very regularly disengaged, and acetate of barium is at the same time formed. The operation may be performed in an ordinary retort or flask with tube. The gas evolved is a mixture of exactly two volumes of carbonic acid, absorbable by potash, and one volume of a non-absorbable gas, which possesses the composition, and presents all the characters of methylide of methyl, 2(H), or hydride of ethyl. Methyl may, therefore, be prepared as easily as any other gas. The reaction by virtue of which it is obtained is accurately expressed by the equation :2{0,H; } 0 ] + 2Ba0 ̧ =¤ ̧Ð ̧ +€2H2+2 [ B2 [€ H3O 4 vols. 2 vols. Ва MM. Victor De Laynes and G. Esperandieu presented a note "On the Preparation, and some Properties, of Pyrogallic Acid." By the application of heat gallic acid is split up into carbonic and pyrogallic acids, and theoretically 100 parts of gallic acid should yield 74'1 of pyrogallic acid. In practice, however, the authors say that only 25 per cent. is obtained. Liebig, by carefully heating gallic acid mixed with pumice-stone in an oil bath, and carrying away the sublimed product by a current of carbonic acid, only procured from 31 to 32 per cent. of pyrogallic acid. The authors, therefore, had recourse to heating gallic acid in a closed vessel. They employed a sort of Papin's digester made of bronze, in which they placed gallic acid with two or three times its weight of water. They then applied heat, and raised the temperature to 210° C., and kept it at this point for half an hour. The whole operation lasted from an hour and a-half to two hours. The result was an almost colourless solution of pyrogallic acid, which, on evaporation, yielded an amber-coloured crystalline mass. The product was rather more than the theoretical amount, in consequence of the retention of a small quantity of water by the pyrogallic acid. NOTICES OF BOOKS. Practice with Science: a Series of Agricultural Papers. Part 1. July, 1005. London: Longman, Green, and Co. “PRACTICE WITH SCIENCE" is the promising and sugges tive title of a new serial, whose appearance, we believe, all intelligent agriculturists will hail with delight. Empiricism in agriculture is passing away; but the science is not yet fully understood and developed. Farmers are, for the most part, before any other class, "practical men," and are only convinced of a scientific truth by the results in quarters of grain or stones of flesh. The mere title of this book-suggesting, as it does, details of the practical results of the applications of science-will therefore attract numerous readers; and this first part, at all events, will not disappoint them. Although there are but two papers in this part that call for particular notice from us, we may express our belief that the whole of them will be read with interest. The first, on Agricultural Education, by the Principal of Cirencester College, is a good common-sense article, advocating a sound scientific but special training for the agriculturist. The next is on Agricultural Drainage, by Mr. J. Bailey Denton, whose name is a sufficient guarantee for the excellence of the article. Mr. Ransome's name, also, is enough as an authority on Ploughs and Ploughing. We might go through all the papers making a similar remark. The subjects are very varied, ranging, we may say, from the profits and management of Farm-yard Poultry up to Leases, on which there is a valuable lecture by Mr. R. &. Welford, Judge of the Birminghain County Court. periments," by Professor Church, and "Notes on some of The papers we may notice are, a "Report of Wheat Exthe Circumstances which Determine the Agricultural Value of the Natural Phosphates, with a brief account of the present methods of analysing them," by Robert Warington, jun. The latter part of this second shall transfer to our pages on another occasion. paper we Have we any ready method of selecting corn for seed, so Professor Church has sought an answer to the question, as to enable us to get a larger and better crop? and he Use the densest grains believes he has found the answer. for seed. The following is the process by which the Professor separated the grains according to their density. The wheat was first wetted with a solution of mercuric chloride to remove the adherent air. They were then partially dried with a cloth. The seed was then placed in a capacious cylinder, and several gallons of a solution of chloride of calcium, sp. gr. 1247 poured upon it. The liquid was gently stirred for a few minutes, the seed allowed time for subsidence, and the floating grains finally removed in a perforated ladle. The denser seed was then separated, washed, and dried. It is necessary, the Professor states, to vary a little the strength of the calcium chloride solution according to the kind of wheat operated upon; the average strength employed corresponded to about 30 per cent. of the chloride, and to a density of 127. Experiments were made with four kinds of wheat, the denser seeds being selected as above, and the results are given in a table. We must content ourselves with quoting Mr. Church's conclusions :— "1. That an average extra return of about thirteen shillings per acre may be obtained by submitting the seed this paper. sown to the particular process of selection mentioned in to secure the extra return. In practice, the exclusion of 2. That a very high standard of density is not required 20 per cent. of the seed-wheat will probably be sufficient to ensure this result. "3. That the process of selection by density is easy and inexpensive." We hope to learn next year that this process has been extensively applied, and been found as advantageous as in these experiments. We shall return to Mr. Warington's paper; and we conclude now by strongly recommending "Practice with Science" to the notice of every agriculturist. |