INDUSTRIAL PROGRESS DURING THE YEAR 1876. xxxv 



The correction of hygrometric observations for the altitude of sta- 

 tions above sea-level, which is very large at altitudes exceeding a 

 few thousand feet, but which is frequently neglected by meteorolog- 

 ical observers, can be made very easily by means of the table pub- 

 lished by Hotier in the last annual report of the Commission du Pic 

 du Midi. 



The ninth annual report of the Warden of the Standards in Lon- 

 don gives, besides current work, a special account of the recent re- 

 verification of official standards of weight, capacity, and length. 

 Among the appendices a description is given of the new balance 

 designed by Mendeleff, one peculiarity of which is that it has very 

 short arms, although adapted to wxigh large masses. 



Some very interesting aerodynamic experiments have been sug- 

 gested by Professor Tait in connection with the dead heat arrange- 

 ment proposed by Sir William Thompson for delicate chemical bal- 

 ances. This arrangement is very sensitive to the least current of air 

 blowing upon it, and may be made the means of investigating the 

 diminution of pressure that takes place in a direction at right angles 

 to any current of air. 



A series of observations has been instituted by J. W. Osborne, 

 of Washington, who has proposed that observers keep a record 

 of the temperature and its changes so far as they are sensible to the 

 human body, and can be estimated without regard to thermome- 

 ters or other instruments. He has, therefore, provided a scale of 

 terms from one, which is unendurable cold, to twenty, which is un- 

 endurable heat. A large number of observers having volunteered 

 to assist him in Washington and its vicinity, he has been able to 

 show that very satisfactory agreements exist between the estimates 

 of different observers, and that the diurnal and annual changes in 

 sensible temperature are well marked. From such observations as 

 these he hopes to obtain an idea of the relative climates of clifterent 

 portions of the world, so far as they affect the human system, more 

 satisfactory than can be deduced from the study of ordinary mete- 

 orological and instrumental records. Observers in Washington and 

 in Ohio have co-operated in this system. 



Professor Wild, of St. Petersburg, has introduced a new form of 

 siphon barometer, which consists essentially of two vertical tubes 

 firmly inserted into the closed cisterns. It is said by him to be more 

 accurate than the ordinary cistern barometers, although also heavier 

 and more costly. 



The same physicist has also published a careful comparison of Avet 

 and dry bulb thermometers, observed both with and without a brisk 

 artificial ventilation. He finds the effect of the artificial currents 

 quite insignificant as regards the dry bulb ; but they, of course, low- 

 er the wet bulb, and sufficiently in the summer time to diminish the 

 apparent humidity. On the average, however, he concludes that the 



