not, and a little of their milk mixed with the others for it was not with the milk of one cow alone they had to deal-would soon raise the low figure. He wished Mr. Dyer had given the ash, and hoped it would be added to the paper before it was published. He always liked to see the ash, because he had found that where the ash was taken it was a good guide a much better guide than many analysts thought and the ash corresponded with the solids not fat to such an extent that any analyst who was desirous of checking the work of his assistant could do so very well by those two determinations alone. As regards a standard Dr. Muter did not think the Society's standard had been at all affected, because it was an open question whether to starve a cow was not simply another way of adulterating the milk. It they were to go round England and milk one thousand cows, and tabulate the analyses, and take only those in which the solids not fat, fat, and the ash, agreed—rejecting those analyses in which either were only a point or two out-he ventured to say that they would not find twenty that would fall below 8.9, and not more than one which would fall below the Society's standard, which he did not think ought to be lower than it was. In conclusion he pointed out the importance of not relying on any one constituent, but of judging on the analytical results as a whole, and disregarding a slight departure from the average of solids not fat if compensated for by an increase in fat itself. Dr. Dupré said he had repeatedly given certificates in cases where the solids not fat had been 8.6 or 8·5, and the vendors had paid the fines imposed on conviction. He considered the specific gravity of a milk was of much more importance than many analysts seemed to consider. It appeared to him that the specific gravity of some of the milks referred to did not correspond with some of the other figures. His experience was that a milk of over 1030 specific gravity was almost always up to the Society's standard. specific gravity should always be given, as it was, he thought, the best guide they could have of the correctness of the analysis. Dr. Dupré also thought that no analyses should be published without being duplicated, and also that the process used should always be stated. The Mr. Hohner said there was, undoubtedly, some proof that the solids not fat fell below 9.0 in some cases, and if that figure was a little too high then 2.5 was rather low for the fat. If any alteration was made at all it must not only be in the solids not fat, but the fat must be raised. Mr. Dyer, in reply, said that very many of his analyses were made in duplicate and some in triplicate. As to the ash, no doubt it was very important, but he thought Dr. Muter went a little too far in saying that, if the ash did not exactly accord, it proved the analysis incorrect, because nature did sometimes vary her operations. THE WORK DONE BY PUBLIC ANALYSTS UNDER THE SALE OF FOOD AND DRUGS ACTS DURING 1880. In accordance with the custom we have adopted for several years past, we have prepared forms for collecting these details, and have sent them, we believe, to nearly every Public Analyst in the United Kingdom. We have received a very large number of the returns and are collating them for publication in our May number. If any Public Analysts who have not received these forms will send a post card to the publishers, copies shall be sent to them at once. We shall, however, be glad to have them returned to us as early in the month as possible. REVIEW. Report of the Annual Meeting of the British Association at Swansea. This is a handy little reprint of the most important papers read at the Meeting, with notes of the discussions thereon. These notes are well put together and add to the value of the pamphlet. BAKING POWDERS IN THE UNITED STATES. From the New York Tribune. INTERESTING TESTS MADE BY THE GOVERNMENT CHEMIST. DR. Edward G. Love, the present Analytical Chemist for the Government of the United States has recently made some interesting experiments as to the comparative value of baking powders. Dr. Love's tests were made to determine what brands are the most economical to use. And as their capacity lies in their leavening power, tests were directed solely to ascertain the available gas of each powder. Dr. Love's report gives the following: "The prices at which baking powders are sold to consumers I find to be usually 50 cents per pound. I have therefore calculated their relative commercial values according to the volume of gas yielded on a basis of 50 cents cost per pound." NOTE. "I regard all alum powders as very unwholesome. Phosphate and tartaric acid powders liberate their gas too freely in process of baking, or under varying climatic changes suffer deterioration." PRIVATE WELLS OF SOUTHAMPTON. THE following are figures obtained from analysis of a sample of water taken from a private well in Southampton, the water at the time being in daily use for all domestic purposes. It is very remarkable from the enormous amount of saline ammonia present, and is an example of the fearful pollution of which town wells are liable. The water was fairly presentable to the eye and was not unpalatable; the distillate from carbonate of soda smelled strongly ammoniacal, and, of course, gave a strong alkaline reaction. Parts per 100,000: Free NH,. Albumd. NH,. Nitrates. N. Cl. P,0 5.68 ...... 0.0332 ...... Solids. Per. H. Total hardness. 14.5 ...... A. ANGELL. 1.9026 ...... 2.2..v.h. traces. 41.7 Microscopical examination-Starch grains, paper, animal hairs. THE ANALYSES OF THE PUBLIC WATER SUPPLIES OF ENGLAND. WITH this month's issue of the Society's water reports we publish the first instalment of a periodical series of analyses of the water from the sources of supply. It is obvious that as many companies have various different sources of supply-sometimes as many as eight or ten-we cannot at present undertake to publish the reports on all of these monthly; but an occasional analysis of each will throw, we hope, much additional light on the causes of the variations in the character of the water as delivered, and may, cases, lead to the condemnation and abandonment of a bad spring or well. in some The uniform system of analysis has already been productive of much good in enabling analyses to be more accurately compared; and the Water Committee are now engaged, under the direction of the Society, in amplifying the instructions so as to provide for every detail in the analytical work, and ensure such data as shall enable concurrent opinions to be given in every case. These amplified instructions will be published in THE ANALYST as rapidly as possible from month to month. It is not at present in the view of the Committee to introduce any new process; but in order to make the instructions as complete as possible they are considering, and as far as possible testing, any suggestions that may be made with a view to rendering the instructions complete. PROVINCIAL TOWNS. Dublin is supplied with water taken from an artificial lake or reservoir about 26 miles distant from the city, and situated in the mountains of the county of Wicklow. It is filtered at the reservoir, but the supply to the city is taken from an uncovered service reservoir, about five miles from the city. It supplies abont 335,000 persons, and the consumption is about 30 gallons per head per day. Edinburgh. In 1824 water was brought from Crawley springs and Glencone Burn, in the centre valley of the Pentland hills, forming a large compensation reservoir in that valley. This new supply gave an addition of 250 cubic feet a minute, or 2,250,000 gallons a day, or in all 290 feet a minute. Additional water was brought in from the Barelaw Liston Shields and Blacksprings on the north side of the Pentland, and from additional burn water which required the construction of large reservoirs, chiefly for compensation and the enlargement of Glencone reservoirs. Those works were finished in 1852. This gave an additional supply of 230 cubic feet a minute. There were now seven reservoirs having an aggregate capacity of 174,000,000 cubic feet. In 1856 an additional supply of spring water was brought in from Colyium and North Liston Shiels on the north side of the Pentland, at the distance of about 14 miles, giving an increase of about 250 cubic feet a minute; and requiring additional compensation storage of 90,000,000 cubic feet. In 1868 a further supply of spring water was brought from Crosswood also on the north side of the Pentland hills and 20 miles from Edinburgh, making an addition of 125 cubic feet a minute, and requiring a compensation reservoir of about 28,000,000 cubic feet, thus making a total storage of 292,000,000 cubic feet, and a total town supply of about 900 cubic feet a minute, or 8,100,000 gallons a day. The cost of the works up to this time was about £435,000. The Moorfoot scheme, which has just been introduced, will double the former supply; but at present about 1400 cubic feet a minute, equal to about 12,600,000 gallons a day, from all sources is found sufficient. The works are from 14 to 17 miles south from Edinburgh, and there are two store reservoirs having a capacity of 312,000,000 cubic feet, and two compensation reservoirs, viz., one of 44,000,000 and one of 48,000,000, the latter not yet constructed. Dalkeith and Musselburgh and other neighbouring villages are being supplied from the Edinburgh works. Leicester is supplied with water from two sources, viz., Thornton and Cropstone. The strata of the watersheds consists chiefly of slate. The storage reservoir at Thornton (11 miles from Leicester) contains about 273,000,000 gallons. The storage reservoir at Cropstone (five miles from Leicester) contains 500,000,000 gallons. The water is filtered. From Thornton it is sent by gravitation in pipes. At Cropstone, after filtration, the water is pumped into service reservoirs, from which the town is supplied by gravitation. The daily consumption is about 3,000,000 gallons, of which half comes from Thornton. Manchester. The water used for the supply of Manchester is collected from an area of drainage ground of 19,300 statute acres, at and near Woodhead, a distance of about 18 miles from the centre of Manchester. There are 10 reservoirs extending between the one at Woodhead which is the second largest and furthest from Manchester, and the one at Gorton which is the nearest to (about four miles from) Manchester. These reservoirs vary in depth from 20 to 72 feet, and hold from 53,000,000 to 1,474,000,000 gallons. The whole of the reservoirs together hold 4,544,000,000 gallons, and one reservoir is in course of construction at Denton, which is calculated to hold 1,860,000,000 gallons. The highest reservoir-which is the one at Woodhead-is 650 feet above the level of the ground at the Manchester Exchange; and the lowest, at Gorton, is 125 feet above that level. The average quantity of water supplied per day during the year 1880 was 17,998,758 gallons. The drainage area at Woodhead from which the water is collected is formed of the lower millstone grit, also called the "Kinder Scout grit." These beds are interlaid with shale beds, and the flat topped summits of the hills are largely covered with peat, which, however, does not extend to the slopes of the valleys. Newcastle and Gateshead. The supply is obtained from reservoirs at Whittle Dean, 12 miles distant from Newcastle-upon-Tyne, and at Hallington 22 miles distant. The capacity of these reservoirs is 1,200,000,000 gallons, and the water is obtained from Whittleburn, Pout, Fair Spring, Mootlawburn, Hallowell, Smallburn, and Hallington North, and Eastburns, the total drainage area of these streams being 17,000 acres, chiefly pasture land. The reservoirs at Hallington and Whittle Dean are connected by an open aqueduct and tunnel, 10 miles in length. The water is conveyed by an open aqueduct and tunnel to filter beds at Throckley, five miles from the town, and is thence distributed by 30-inch and 24-inch metal pipes. The supply is by gravitation to a height of about 200 feet, the higher portions of Newcastle being supplied from a reservoir at Fenham into which the water is pumped from a service reservoir at Benwell, while the higher portions of Gateshead are supplied from a reservoir at Carr's Hill, to which the water is raised from a pumping station on Windmill Hills. There is also a pumping station on the river Tyne at North Wylam, from which a supply can be obtained for manufacturing purposes by a separate line of pipes. In addition to these works two reservoirs are being constructed on SOCIETY OF PUBLIC ANALYSTS. Analyses of English Public Water Supplies in March, 1881. Leicester 3000 none 0030 none none 12.2° 4.4° 24.80 0520 0005 0024 0035 h. traces 6382 0036 0077 0272 0200 23.04 diatoms and ferric oxide 0274 2.0° 2.0° 5.70 peaty mttr. movg. orgsm satisfactory peaty matter traces 1550 0004 0140 0040 1625 8.0° 4.2° 14.62 confervæ dmids. veg. deb. *One sample is from the Upper and one from the Lower part of the town. L. Archbutt. A. H. Allen. C. A. Cameron. J. Falconer King. F. P. Perkins. A. Ashby. G, Jarmain. W. Johnstone. T. Fairley. satisfactory 0490 15.9° 1.5° 22.80 0014 17.8° 5.5° 24.50 4.7° 11.76 7.1° 27.44 7.5° 27.40 sand, &c. v. s. mineral matter s. clay veget. matter and sand 6.5° 23.0 sand, vegetable fibre 3.2° 19.70 1686 2.9° 5.04 |