- Email: [email protected]
A new quantitative reagent
376
CURRENT
TOPICS.
[J. F. I.
glass rods, was kept at a negative potential of 3,000 volts. It was then quickly wound up. Three minutes after it had been in the air it was put mto the ionizing chamber of an electrometer whose rate of discharge was observed. One experiment a dav was performed for the eight months from October to May. No difference in the effect was found by changing the voltage of the exposed wire from 1500 to 5000. The unit of activity of the atmosphere was that present when one metre of the wire discharged the electrometer one volt per hour. In such units the average monthly activity rose from jar in October to a maximum of 550 in January, from which it descended to 250 in May. “ On the whole, the activity in Lucknow is far greater than that observed by Simpson and Gockel in Europe.” From a comparison of activity with the height of the barometer it is manifest that in India an increase of activity is generally accompanied by a fall of the barometer and vice versa.. This is comprehensible on the view that the radio-active content of the atmosphere is due to the escape of active material from the soil. A reduction of the air pressure would facilitate this motion. It is, however, clear that at least a part of the radio-active effect depends on something coming from above, for “ cloudy weather always shows small radio-activity, while clear weather is attended with higher values.” The denser cumulus clouds reduce the activity more than cirrus clouds. Such observations are of interest in connection with Millikan’s penetrating radiation. G. F. S. Centenary of the American Journal of Pharmacy.-In December, 1925, the Avnerican Journal of Pharmacy celebrated the onehun$redth anniversary of the publication of its first number in During the century of its existence, the journal Decemb’er, 1825. has been published by the Philadelphia College of Pharmacy and Science for the advancement of pharmacy and the allied sciences, and the promotion of correlated education and research. It is the oldest pharmaceutical periodical published in the English language, and was for many years the only pharmaceutical journal in the United States. Its editors and the contributors to its pages have been eminent in The centenary number contains a pharmacy and the allied sciences. series of papers which summarize th’e advances in the arts and sciences, at home and’ abroad, during the past century. J. S. II. A New Quantitative Reagent.-Citarin, the sodium salt of a complex derivative of citric acid, was introduced in 1901 by the Elberfeld Company as a therapeutic agent. In 1917, Vanino reported in the Kolloid-Zeitsch. (1917, 20, 122) its use in colloid chemistry. Recently Vanino and Guyot have studied its application as a reagent for the determination of reducible metals. Their results, which as yet have been found satisfactory only with silver and gold, are reported in the Bcr. d. deztf. Phnrvtz. Gesell. (1926, 36, 98). When mixed with water, the salt undergoes hydrolysis with separation of formaldehyde and it was, therefore, inferred that reducible metals
woultl IX set free. Decinormal silver nitrate was mixed with citaril? _;olution and sodium hydroxide of similar strength, heatetl for thirt! The l)reminutes on the water-bath and allowed to stand overnight. cipitate was collected on a suitable filter, washed and dried (at from TIO0 to 120’). A similar method was applied to gold chloride solu-The test analyses submitted show very satisfactory data. tion. Ksperiments with bismuth have so far not yielded useful results. I-I. I_. L. and A New Stroboscopic Device with Strong Illumination. A. SEGUIX. (Comptcs Readus, Oct. 26, 1()25.)-h long ago as 1873 Crova knew the use of a Geissler tube for the production of \Vith either a vibratintermittent illumination at controlled intervals. ing or a rotating interrupter, the arc formed by breaking the current limited the strength of the current in the primary, and consequently in the secondary coil also, so that the available current through the tube produced but feeble flashes of light. To avoid this hampering dependence of the intensity of light upon the current capacity of the interrupter, in the new apparatus the illumination comes from the discharge of a strong battery of condensers through a neon tube. This discharge cannot pass by its own voltage but must wait to be set off by an induced current due to the interruption of a current by the timing device. Th e intensity of the momentarv illumination It can In addition be can, therefore, be made as great as is desired. caused to be practically instantaneous. In one case two marks, one mm. apart, could be clearly seen on a disc, illuminated by this device, even when it was rotating so that its periphery had a speed of IOO mm. per sec. The strong intensity of the flashes of light produced in the tube is of value in studying the motion and vibration of large and somewhat inaccessible machinery. G. F. s. The Thirteen-month Calendar. (U. S. Department of Agriculture, Clip Sheet, No. 397, Feb. I, r926.)-Fresh stimulus has recently been given to the reform of the calendar by the action of the committee of inquiry of the League of Nations in calling representatives of the Roman, Greek, and other orthodox churches of the East, the Anglican Church of Great Britain, and about 100 Protestant churches to discuss the advisability of making Easter a fixed instead of a movable date, dependent on the full moon. The first or second Sunday in April has been suggested. Further sessions of the committee of inquiry are to be held soon to make definite recommendations to the League of Xations regarcling plans for calendar reform. Enthusiastic support has been given in many quarters to the plan that would divide the year into thirteen twenty-eight-day months, with an extra day at the end of the last week in December. Every four years a leap-year day would be inserted at the end of June. The change, it is said, could be made easily on January I, 1928, as that will be Sunday. Prof. C. F. Marvin, Chief of the U. S. 1Veather Bureau, indorses
CURRENT
TOPICS.
[J. F. I.
glass rods, was kept at a negative potential of 3,000 volts. It was then quickly wound up. Three minutes after it had been in the air it was put mto the ionizing chamber of an electrometer whose rate of discharge was observed. One experiment a dav was performed for the eight months from October to May. No difference in the effect was found by changing the voltage of the exposed wire from 1500 to 5000. The unit of activity of the atmosphere was that present when one metre of the wire discharged the electrometer one volt per hour. In such units the average monthly activity rose from jar in October to a maximum of 550 in January, from which it descended to 250 in May. “ On the whole, the activity in Lucknow is far greater than that observed by Simpson and Gockel in Europe.” From a comparison of activity with the height of the barometer it is manifest that in India an increase of activity is generally accompanied by a fall of the barometer and vice versa.. This is comprehensible on the view that the radio-active content of the atmosphere is due to the escape of active material from the soil. A reduction of the air pressure would facilitate this motion. It is, however, clear that at least a part of the radio-active effect depends on something coming from above, for “ cloudy weather always shows small radio-activity, while clear weather is attended with higher values.” The denser cumulus clouds reduce the activity more than cirrus clouds. Such observations are of interest in connection with Millikan’s penetrating radiation. G. F. S. Centenary of the American Journal of Pharmacy.-In December, 1925, the Avnerican Journal of Pharmacy celebrated the onehun$redth anniversary of the publication of its first number in During the century of its existence, the journal Decemb’er, 1825. has been published by the Philadelphia College of Pharmacy and Science for the advancement of pharmacy and the allied sciences, and the promotion of correlated education and research. It is the oldest pharmaceutical periodical published in the English language, and was for many years the only pharmaceutical journal in the United States. Its editors and the contributors to its pages have been eminent in The centenary number contains a pharmacy and the allied sciences. series of papers which summarize th’e advances in the arts and sciences, at home and’ abroad, during the past century. J. S. II. A New Quantitative Reagent.-Citarin, the sodium salt of a complex derivative of citric acid, was introduced in 1901 by the Elberfeld Company as a therapeutic agent. In 1917, Vanino reported in the Kolloid-Zeitsch. (1917, 20, 122) its use in colloid chemistry. Recently Vanino and Guyot have studied its application as a reagent for the determination of reducible metals. Their results, which as yet have been found satisfactory only with silver and gold, are reported in the Bcr. d. deztf. Phnrvtz. Gesell. (1926, 36, 98). When mixed with water, the salt undergoes hydrolysis with separation of formaldehyde and it was, therefore, inferred that reducible metals
woultl IX set free. Decinormal silver nitrate was mixed with citaril? _;olution and sodium hydroxide of similar strength, heatetl for thirt! The l)reminutes on the water-bath and allowed to stand overnight. cipitate was collected on a suitable filter, washed and dried (at from TIO0 to 120’). A similar method was applied to gold chloride solu-The test analyses submitted show very satisfactory data. tion. Ksperiments with bismuth have so far not yielded useful results. I-I. I_. L. and A New Stroboscopic Device with Strong Illumination. A. SEGUIX. (Comptcs Readus, Oct. 26, 1()25.)-h long ago as 1873 Crova knew the use of a Geissler tube for the production of \Vith either a vibratintermittent illumination at controlled intervals. ing or a rotating interrupter, the arc formed by breaking the current limited the strength of the current in the primary, and consequently in the secondary coil also, so that the available current through the tube produced but feeble flashes of light. To avoid this hampering dependence of the intensity of light upon the current capacity of the interrupter, in the new apparatus the illumination comes from the discharge of a strong battery of condensers through a neon tube. This discharge cannot pass by its own voltage but must wait to be set off by an induced current due to the interruption of a current by the timing device. Th e intensity of the momentarv illumination It can In addition be can, therefore, be made as great as is desired. caused to be practically instantaneous. In one case two marks, one mm. apart, could be clearly seen on a disc, illuminated by this device, even when it was rotating so that its periphery had a speed of IOO mm. per sec. The strong intensity of the flashes of light produced in the tube is of value in studying the motion and vibration of large and somewhat inaccessible machinery. G. F. s. The Thirteen-month Calendar. (U. S. Department of Agriculture, Clip Sheet, No. 397, Feb. I, r926.)-Fresh stimulus has recently been given to the reform of the calendar by the action of the committee of inquiry of the League of Nations in calling representatives of the Roman, Greek, and other orthodox churches of the East, the Anglican Church of Great Britain, and about 100 Protestant churches to discuss the advisability of making Easter a fixed instead of a movable date, dependent on the full moon. The first or second Sunday in April has been suggested. Further sessions of the committee of inquiry are to be held soon to make definite recommendations to the League of Xations regarcling plans for calendar reform. Enthusiastic support has been given in many quarters to the plan that would divide the year into thirteen twenty-eight-day months, with an extra day at the end of the last week in December. Every four years a leap-year day would be inserted at the end of June. The change, it is said, could be made easily on January I, 1928, as that will be Sunday. Prof. C. F. Marvin, Chief of the U. S. 1Veather Bureau, indorses