374 THE POPULAR SCIENCE MONTHLY. 



popular as possible ; and it particularly desires to be useful to the phy- 

 sicians, meteorologists, and the commercial manufacturers who have 

 occasion to use fairly accurate thermometers. The testing of illumi- 

 nating oils, the manufacture of spirits and ethers, and the numerous 

 operations of the chemical laboratory, require thermometers of consid- 

 erable accuracy, and for the benefit of persons using such the observa- 

 tory has issued a circular which will be mailed on application. 



Thermometers may be sent by mail or express, directed to the Win- 

 chester Observatory, New Haven, Connecticut. If they are sent by mail 

 (and nothing larger than a clinical thermometer should be), they ought 

 to be packed in a wooden box, in tissue-paper. In whatever man- 

 ner they are sent, a little care taken in packing them in soft paper will 

 materially lessen the risk of accident. Ordinary thermometers are re- 

 turned to the senders, with certificates stating their deviation from the 

 true mercurial standard for every ten degrees, within a few days from 

 the date of their reception. Standards require from a week to a month 

 for their investigation, depending upon the degree of precision desired 

 in the final certificates. 



The oflicial circular of the observatory contains detailed informa- 

 tion relating to the supervision of hospital thermometers and the facili- 

 ties offered to makers. There is no good reason why any maker should 

 not furnish, with any thermometer sold, a certificate stating the errors 

 of that particular instrument. That the service will be a popular one 

 is shown by the fact that already about five hundred thermometers 

 have been sent to the observatory for verification, and not the least 

 benefit will be that the errors of every thermometer issued with a 

 certificate will be on file at the observatory, and this will be of par- 

 ticular value in cases where a uniformity of data is desired, as in the 

 case of the United States Signal Service, or the observations made by 

 isolated meteorologists in different parts of the country. 







mDIGESTION AS A CAUSE OF NEEYOUS DEPKES- 



SION. 



By T. LAUDER BEUNTON, M. D., F. E. S. 

 II. 



BUT bile is not the only substance which produces a depressing 

 effect upon the circulation when absorbed into it from the portal 

 system. I have already mentioned that certain albuminous products 

 of intestinal digestion and peptones occasionally make their appear- 

 ance in the urine. Among the former is an albuminous substance, 

 not precipitated by boiling, but by nitric acid in the cold. . This sub- 



