Is it possible to express the pleasantness or unpleasantness of a climate on a scientific scale? asks Knowledge. Capt. W. F. Tyler, F.R.Met.Soc., has attempted to form such a scale. Concluding that the two dominant factors influencing our sensation of comfort are temperature and humidity, he has coined the word hyther"--apparently from the first syllables of hygrometer and thermometer"'--to indicate this joint effect. A perfectly pleasant day is registered 0 on this hyther scale, and an intolerably oppressive one as 10. Capt. Tyler's own observations of hyther extend over several years, but in the end of the summer of 1902, he was able to get the co-operation of eleven other observers for the systematic observation of hyther throughout the month of August. The results of the comparison showed that most persons would require a considerable amount of practice before their observations could be considered trustworthy, but some approach was made toward the establishment of a definite law connecting the temperature and humidity with the hyther sensation. At the same time there were indications that some other factors, possibly barometric pressure or electric conditions, had an appreciable influence upon the sensation. The subject seems well worth working out on a more extended scale. When an alkaline solution of gold is treated with different reducing agents, a strongly colored blue or red liquid is obtained which is supposed to contain the gold in a colloidal state. M. Hanriot, of Paris, took up a~ series of researches upon this question. He had previously shown that the different varieties of colloidal silver formed as many chemically distinct species having different properties, and wished to see whether gold did not act in the same way. Under the name of colloidal gold, Heinrich describes solutions which he obtained by treating chloride of gold with different reducing phenols such as pyrocatechine and hydrochinon. M. Hanriot formed a solution of colloidal gold by dissolving one gramme of chloride of gold in one liter of distilled water. This he boiled with enough carbonate of soda to give a slightly alkaline reaction. He then poured in a 1.1 per cent cold solution of pyrocatechine to the amount of 300 cubic centimeters. This formed a red color which soon changed to violet. Dilute sulphuric acid was added drop by drop until the solution became slightly acid. The liquid turns blue in this case and deposits a blue precipitate at the end of a certain time. After washing, the powder is dissolved in dilute ammonia and again precipitated by sulphuric acid, avoiding excess of the latter. This compound is a violet-blue powder which is very slightly soluble in pure water, but is insoluble in a slight excess of sulphuric or nitric acid or their alkaline salts. On the contrary it dissolves easily in alkalis, especially ammonia or carbonate of soda. The excess of ammonia can be expelled from such solution by boiling, but this does not throw down the gold. Strong acids, however, will cause a precipitate in this case. The latter precipitate is found to be hydrated, and water forms part of its constitution. Thus, when dried at 100 deg. C., it loses its solubility in alkalis. The analysis of the body, dried ' at 40 deg. C., is .as follows: Water (which is expelled at 100 deg.) 2.04 parts; loss at red heat, 6.31; gold, 91.53; SO3, 0.39. This compound is but little altered by acids. In alkaline solution it soon deposits metallic gold, while the liquid takes a brown color. It seems to contain an organic matter which is not easy to determine. Colloidal gold is not soluble in mercury. When calcined it gives off carbon monoxide and dioxide gases, and hydrogen. A point to be observed is that this body is precipitated from a solution by acids and in this state is insoluble, but is re-dissolved by adding an alkali. It is therefore not to be admitted that the solutions are formed of fine particles of gold which are not agglomerated, seeing that this body keeps its solubility even when in the solid state, as above shown. Besides, it shows acid properties and forms a series of salts with the heavy metals which are either soluble or insoluble, each having individual properties. The retirement of William K. Jenne, of Wyckoff, Seamans&Benedict, was marked by a complimentary dinner given to him at the Waldorf-Astoria, Monday, November 28, and the tendering of a loving cup. To Mr. Jenne, more than any one else, is the development of the ,modern typewriter due. It was in 1873 that the first crude model of the typewriter was taken to the !gun works of E. Remington&Sons at Ilion. The of the invention was placed in charge of Mr., Jenne. In Mr. Jenne's charge, it ever since remained. Through his labors the machine has steadily advanced through all the successive stages of improvement, from the first crude ideas of the inventors to the Remington models of the present day. During this time Mr. Jenne has not only seen the development of the typewriter, to which he devoted the labors of his life, but has also witnessed its progress from an absolutely untried experiment to the necessity it has now become in the world's work.