it is rare or plentiful, local or occurring over a wide area. Samples of wood are often brought, but generally without any means of identification except a native name; and it must be borne in mind that native names are apt to be inisleading; they may be invented on the spur of the moment to satisfy the white man's craving for information or when genuine are often applied to more than one species. A large proportion of the more extensive collections are due to German enterprise, and the best representation of this work is naturally to be found in Germany, though it is only fair to state that the German botanists have been generous in lending material for work or comparison. The botanical investigation of German East Africa and the Cameroons has been carried out by well-trained botanists and collectors, and the results of their work published both from botanical and economic points of view. I may refer to the large volume on German East Africa, which contains not only general account of the vegetation and a systematic st of the genera and species comprising the flora, but also an account of the plants of economic value classified according to their uses. The exploration of the Belgian Congo has been seriously undertaken by the Belglan Government, and a number of large and extensively illus.rated botanical memoirs have been issued. Some of us may be familiar with the fine Congo Museum near Brussels. It is time that pioneer work gave place to systematic botanical exploration of our tropical possessions, and the preparation of handy working floras and economic hand books. Work of botanical exploration should be full of interest to the young botanist. But if he is to make the best use of time and opportunity he must have had a proper course of training. After completing his general botanical course, which should naturally include an introduction to the principles of classification, he should work for a time in a large Herbarium, and thus acquire a knowledge of the details of systematic work and also of the general outlines of the flora of the area which he is to visit later. He should then be given a definite piece of work in the botanical survey of From the collated results of such work convenient handbooks on the botanical resources of regions open to British enterprise could be compiled. There will be plenty of work for the systematist who cannot leave home. The ultimate elaboration of the floristic work must be done in the Herbarium with its associated library. the area. There is also need of a careful monographic stndy of genera of economic value which would be best done by the experienced systematist at home, given a plentiful supply of carefully collected and annotated material. An example of such is the systematic account of the species of Sanseviera by Mr. N. E. Brown, recently issued at Kew. Closely allied species or varieties of one and the same species may differ greatly in economic value, and the work of the monogr.pher is to discover and diagnose these different forms, and elucidate them for the benefit of the worker in the field. If we are to make the best use of our resources botanical research stations in different parts of the Empire, adequately equipped and under the charge of a capable trained botanist, are a prime necessity. We seem to have been singularly unfortunate, not to say stupid, in the management of some of our tropical stations and botanical establishments. The island of Jamaica is one of the oldest of our tropical possessions. It is easy of access, has a remarkably rich and varied flora, a fine climate, and affords easy access to positions of widely differing altitude. It is interesting to imagine what Germany would have made of it as a station for botanical work if she had occupied it for a few years. The most recent account of the flora which pretends to completeness is by Hans Sloane, whose work antedates the Linnæan era. A flora as complete as available material will allow is now in course of preparation in this country, but the more recent material on which it is based is due to American effort. Comparatively recently a mycologist has been appointed, but there is no Government botanist to initiate botanical exploration or experimental work or to advise on matters of botanical interest. A botanical station ideal for experimental work in tropical botanical problems is a mere appendage of a Department of Agriculture, the Director of which is a chemist. A botanical station for research to be effective must be under the supervision of a well-trained botanist with administrative capacity, who must have at his disposal a well-equipped laboratory and ground for experimental work. He must not be expected to make his station pay its way by selling produce or distributing seedlings and the like; a botanical station is not a market-garden. The Director will be ready to give help and advice on questions of a botanical nature arising locally, and he will be on the look-out for local problems which may afford items of botanical research to visiting students. Means must be adopted to attract the research student, aided if necessary by research scholarships from home. The station should have sufficient Imperial support to avoid the hampering of its utility by local prejudice or ignorance. The permanent staff should include a mycologist and a skilled gardener. The botanical station does not preclude the separate existence of an agricultural station, but the scope of each must be clearly defined, and under normal conditions the two would be mutually helpful. Nor should the botanical station be responsible for work of forestry, though forestry may supply problems of interest and importance for its consideration. Finally, I should like to suggest the holding of an Imperial Botanical Congress at which matters of general and special interest might be discussed. The visit of the British Association to Australia was, I think, helpful to the Australian botanists; it was certainly very helpful and of the greatest interest to those coming from home. Many of the addresses and papers were of considerable interest and value, but of greater value was the opportunity of meeting with one's fellow-workers in different fields, of conversation, discussion, and interchange of ideas, the better realisation of one's limited outlook and the stimulus of new associations. A meeting which brought together home botanists and botanical representatives from oversea portions of our Empire to discuss methods of better utilising our vast resources would be of great interest and supremely helpful. Let us transfer to peace purposes some of the magnificent enthusiasm which has flowed homewards for the defence of the Empire in war. In this brief Address I have tried, however imperfectly, to indicate some lines on which botanists may render useful service to the community. To a large extent it means the further development and extension of existing facilities added to an organised co-operation between botanists themselves and between botanists and the practical and commercial man; this will include an efficient systematic cataloguing of work done and in progress. We do not propose to hand over all our best botanists to the applied branches and to starve pure research, but our aim should be to find a useful career for an increasing number of well-trained botanists, and to ensure that our country and Empire shall make the best use of the results of our research. Incidentally, there will be an increased demand for the teaching botanist, for he will be responsible for laying the foundations. Complaint has been made in the past that there were not enough openings for the trained botanist; but if the responsibilities and opportunities of the science are realised we may say, rather, "Truly the harvest is plentiful, but the labourers are few." Botany is the alma mater of the applied sciences, agriculture, horticulture, forestry, and others; but the alma mater who is to receive the due affection and respect of her offspring must realise and live up to her responsibilities. IN the department of analytical chemistry little has been devised to lighten the manipulative requirements of the chemist. Every operation undertaken requires the utmost skill and patience, whilst often the time expended is out of all proportion to the results obtained. The wash-bottle-the chemist's staff-is ever in his hand, which, when so occupied, is not free for any other operation. The washing of precipitates is one of the greatest timeabsorbing factors in the laboratory. Yet there is no escape from it, demanding as it does the utmost attention and skill; in this way the output of a laboratory is considerably limited. With a view to minimising the loss of time, and thus in FIG. 1. creasing the scope of the chemist, the machine is illustrated in Fig. 1. After thorough and severe tests it has shown itself capable of satisfying this long-felt want, and hence is worthy of the notice of analysts. The machine can carry out quite automatically the washing of any precipitate in a more efficient way than can be done by hand. The constructional details are set out briefly in the following:The apparatus intrinsically is a balance, on one arm of which is fixed a supporting ring for a filter funnel, on the other a movable counterpoise weight and also an electrical commutator. Over the beam is fixed a table carrying two electric motors, shown in diagram as B and C in Fig, 2, one to control through a specially constructed mercury valve (A and B, Fig. 3) the flow of water to a jet which is rotated by the other motor. The two motors are connected to the current supply through the commutator arm A, Fig. 2, in such a way that when the funnel end of the beam is up the water supplied by gravity flow from a flask or tin-lined copper tank, which may be heated if necessary, passes freely to the jet which sprays the water round the edge of the paper containing the precipitate to be washed reposing in the funnel. which is regulated by a screw, is moved into such a posiThe counterpoise weight at the other end of the beam, tion that when sufficient water has flowed into the funnel the increased weight causes the beam to drop, thus shutting off the water supply to the jet, so that no current is wasted during the period it is not required. As the water drips from the funnel the arm supporting it becomes lighter, the beam rises, and water again enters the filter through the rotating jet. In this manner the washing process continues until it is complete. The valve controlling the water supply to the jet is a glass bulb, shown in Fig. 3, containing mercury represented in the figure by shading, fitted with an inlet tube c, which reaches to the bottom of the bulb, and an outlet tube D. When the bulb is in an upright position, as in A, Fig. 3, the water supplied to it cannot flow on account of the resistance of the mercury to it. If the valve be turning through 90°, as in B, Fig. 3, the mercury rolls away from the inlet tube, thus allowing the water a free passage to the outlet D. This bulb is mounted on the machine in such a way that the motor B (Fig. 2), which is reversible, will turn it from the horizontal to the vertical plane and vice versa, as the commutator arm A is raised or lowered. In order to check the rotation of the motor in either direction after it has turned over the valve, it is cut out of circuit by a turn of the wheel o, fixed to the valve on which are mounted two steel contacts, P and R, Fig. 2, capable of alternately dipping into the mercury cups, H and J, so that whilst one is out of circuit contact is made in the other ready for the return journey as soon as the commutator moves over. The apparatus is simple in construction, robust, and with few moving parts. The electric contacts are made by steel rods dipping into steel mercury cups carried on ebonite insulators. The working parts are enclosed from dust and chemical fumes by suitable covers, and when in use appears as in Fig. 1. If it should be required to wash a precipitate, with a predetermined quantity of wash-water, say 200 cc., a small float can be arranged, attached to a cut-out on the main circuit to the apparatus, and this will arrest the washing quite automatically when the amount of water has passed through the filter. Six or twelve of these machines can be mounted together for use in laboratories where a considerable portion of the analyst's time is consumed, as in steel and refractory materials laboratories, in this laborious operation of filter-washing. The current, which is only intermittently used, that is when water is being sprayed into the filter, can be taken from the main power or lighting circuit. The machine shown in the accompanying illustration is actuated by a pressure of 240 volts in conjunction with a suitable resistance. If, however, electric power or lighting is not laid on in the particular laboratory in which the apparatus is to work, a pressure of eight volts from an accumulator is sufficient to control it. The apparatus thus becomes to the chemist a companion of the first order. It gives him a means of completely and effectively washing precipitates with the minimum quantity of hot or cold water in the shortest possible time. As the complete apparatus may be covered during the process of washing dust can be excluded and the contents of the filter-paper left uncontaminated. The machine may be left to complete a washing after the laboratory is closed down for the night. In conjunction with this machine a decanting apparatus, the details of which may be communicated later, can be used, so that large bulks of liquid may be automatically decanted through the filter paper. This apparatus is of especial value in agricultural laboratories, where much time is spent in this operation. It is hoped that this brief account may interest readers in an endeavour to minimise some of the time-absorbing operations of the analytical laboratory. I should like to express my thanks to Messrs. A. Gallenkamp and Co. for the loan of the electro of the block (Fig. 1) used in the illustration. THE FRUIT OF SMILAX ROTUNDIFOLIA. THE fruit of the Smilax rotundifolia, common greenbriar, The Sugar. We placed 150 grms. of the dried fruit in a litre flask attached to an upright condenser, and treated on the hot water-bath with alcohol for twelve weeks. A fresh portion of alcohol was added every few days. Distilled water was then substituted for alcohol, and digestion was continued for eight weeks. The sugar was determined from the two extractions by the use of Fehling's solution. A cc. of the extract was evaporated to dryness to remove the alcohol; it was diluted to 50 cc. with distilled water, and while boiling was titrated with Fehling's solution. We found the sugar to be 7 per cent of the dried fruit. A por ion of the sugar extract was digested some hours on the water-bath with bone-black. By the phenylhydrazine test as outlined by Sherman and Williams (Fourn. Am. Chem. Soc., xxviii., 629) fracture was present. Tests for dextrine gave unsatisfactory results. The Oils. THE terms "fat" and "wax" are commonly applied, more or less indiscriminately, to solid substances which have a greasy feeling to the touch and do not dissolve in water. Physically waxes are regarded as having generally a harder consistency than fats. Chemically fats are usually compounds of the trihydric alcohol, glycerol, C3H5(OH)3. while the waxes are compounds of monohydric alcohols of large molecular weight; for example, cetyl alcohol, C6H33OH, myristic alcohol, C30H61OH, and cholesterol, C27H45OH. The names applied to some of these substances do not lessen the confusion; for example, "wool fat" and "spermaceti" are compounds of cholt sterol and cetyl alcohol, hence are in reality waxes, while "Japan wax," a compound of glycerol, is actually a fat. A fat, such as is indicated above, has among other physical properties a characteristic melting-point. Those which are liquid at ordinary temperatures are called oils. It is of such substances more especially that this communication deals, although reference will be made to cocoanut oil, which may or may not be a solid at ordinary temperatures, therefore technically might be regarded as a fat. The residue of the portion from which the sugar was extracted was dried and weighed. This was placed in a 16 ounce flask, fitted with an inverted condenser, and the oils were separated after digesting with ether four or five It will be understood that the term "oil" as here used weeks. The oils were purified by digesting the ether is not to be associated with the natural or petroleum oils, solution a number of hours with bone-black on the water-i.e., hydrocarbon oils, or the essential oils, both classes of bath. To determine the specific gravity 2 cm. were measured out accurately, and it was found to be o 8585. The saponification equivalent by the Koettstorfer method was found to be 357 14. Rape oil is 350 67. The specific gravity as we determined it is somewhat too low for rape oil. The Ash. We added five different portions. From the first the silica, iron and alumina, calcium, and magnesium were determined; from the second SO; from the third the manganese; from the fourth the phosphate; from the fifth the alkalis. The last were determined by the J. Lawrence Smith method as found in Knight's "Quantitative Analysis." In ashing the fruit, the odour resembles that of burning leaves. It required a comparatively long time, due to the hardness of the seeds. The average weight of ash was 3.06 per cent of the dried fruit. The substances found in the ash were the following: which in general exhibit in a way the physical but not the chemical properties, necessarily, referred to above. Fats are widely distributed in the vegetable and animal kingdoms, and, referring to the former only for the time being, we may say they are primarily glycerides of oleic, palmitic, and stearic acids. These fats are found mainly but not necessarily in the reproductive bodies, such as spores and seeds. They are found in spores, sexual and asexual, of many algae. In angiosperms they are widely distributed, replacing wholly or in part carbohydrates as reserve food material, and they are often associated with protein reserves; for example, in the seed from which colza oil, palm oil, cotton-seed oil, linseed oil, olive oil, and cocoa butter are obtained. It is present, perhaps, as a reserve food material, associated with starch, in some tubers. The starch in the parenchyma of the stem of cer *From the Journal of the Franklin Institute, June, 1916. Presented at a meeting of the Section of Physics and Chemistry, held February 10, 1916. tain plants may be converted into fat during the winter's | favourable-these changes take place within the oilcold, and vice versa when there is a rise of temperature in the summer time. Without venturing into the misty etiology involved we may for our purposes realise the likelihood of the presence of carbohydrates, proteins, and other substances derived therefrom, as gums, &c., in oils obtained from these sources by the various means to be referred to later. here CH2O2C.C17H35 CH2-OP.O.OH.O.C5H13N, OH It is easily broken up by lipase and hydrolysed by boiling with alkalis and acids. We always also,find a small quantity of unsaponifiable residue in fats, which is in the main composed of the monohydric alcohols, cholesterol, C27H45OH, and phytosterol, the latter now being a generic term for a group of allied substances, with formule varying from C27H45OH (sitosterol) to C30H47OH (stigmosterol). Chlolesterol occurs in the bile, brain, and blood of animals, and is the chief alcohol constituent of wool-fat. All vegetable fats contain phytosterol, the amount varying from or to 0.3 per cent, being even higher in the oil obtained from certain peas and beans, especially Calabar beans. The oils are extracted by disintegration of the mass in volving a disruption of the oil-sacs :-(a) with a suitable solvent; (b) rendering by heat, with or without water; (c) or pressure, mechanical, applied when the mass is cold or hot. If the mass extracted be selected and perfectly clean and fresh the oil or fat obtained is usually neutral and "sweet." The exigencies of commercial operation do not admit of these conditions, however, so the oil or fat produced is usually acid and more or less contaminated. The contaminations may be quite normal and natural. They may be bacterial in nature and also contain the very interesting substances known as enzymes (lipase, for example) which induce hydrolysis; that is to say, they will cause any water present to disintegrate the fats (and other bodies) into simpler bodies. This may be facilitated by exposure to air and light, so that a freshly expressed oil that is sweet may soon acquire an unpleasant taste and odour. In some cases we say it becomes rancid, but in all cases the oil develops acidity, and the amount of the acidity of a particular oil is a function of time. Under favourable conditions-and they are usually containing bodies, so that freshly produced oil is usually acid, which acidity increases on keeping. The enzymes are "killed," or decomposed, or at least their directive activity ceases, when they have been exposed to a temperature of about 200° C. It has not been considered a good procedure by the practitioners of the art of oil extraction and refining, however, to heat the oil to such a temperature immediately after its production, but I venture the opinion that the increased development of acidity in crude oil in storage or in transit to a refinery will be materially affected by such treatment. However, it will be necessary to be assured that substances charred or scorched at that temperature are absent. As mentioned above, oils and fats are primarily glycerides of the saturated palmitic (C16H3202) and stearic (C18H3602) acids, associated with the fatty acids of several unsaturated series. For example : 1. Oleic acid, C18H3402. type CnH2n-202. 2. Linoleic acid, C18H32O2, type CnH2n−402. 3. Linolenic acid, C18H3002, type CnHan-602. 4. Clupanodonic acid, C18H2802, typе СnH2и-802. 5. Ricinoleic acid, C18H34O3, type CnH2n-203. The last is an hydroxy acid, which undergoes a particular polymerisation under suitable conditions. Most fatty oils on exposure to the air tend to thicken, due partly to oxidation and partly to polymerisation, or both. Oi's are in fact classified by many according to their drying qualities and tendency toward resinification. These properties play an important part in their utilisation in the arts, and their treatment in refining is materially affected by the time which may have elapsed from actual production to their refining. For example, a freshly produced linseed oil may be profitably refined by a process which is inapplicable if the oil be "aged oil." Oil as stated is normally a liquid, and we usually associate the phenomena of solution with a liquid. To be sure, this is a restricted conception, but will answer for our purposes. In this connection oil acts like water as a fluid. Water in motion carries fine particles suspended through long distances and deposits them in time, when fairly quiet, as we know from the formation of alluvial soils. Water carries certain substances in solution. These latter substances are sometimes coloured and are partly fixed on the filter when that water passes through certain filtering media. For instance, we are able to adsorb Congo red from a water solution with filter-paper. Again, water carries certain substances which do not stop on the filter; they are invisible and show themselves only when we apply the ultra microscope. These finely divided substances, not small enough to be in actual solution, will remain suspended in the water for long periods of time. They are called colloids. By various means, through heat, addition of an acid, an alkali or a salt, by the influence of an electric current, or by the addition of other colloids, these very finely divided substances may be caused to agglomerate; that is, they may be converted into particles of sufficient size to be separated from the fluid by means of a filter. Exactly the same is true of oils. Organic colloid solutions may be viscous; the liquid particles are suspended in a liquid medium. Many of the contaminating substances, referred to here in general, may be suspended in the oil, may be in solution in the oil, or may be in a colloidal condition in the oil. It will, therefore, be quite apparent that crude vegetable and animal oi's contain a variety of impurities traceable to a great variety of causes. The character of the crude oil depends not only upon the kind and part of the vegetable (wood, nut, seed, &c.) and animal (fish, whale, &c.) used, but the quality of the raw material at the time of expressage or extraction (rusting, rotting, fermentation, sprouting, heating, &c.), the method followed, the care exercised in the process, and the conditions to which the oil is subjected prior to its refining. In many cases, in fact, we |