DESIGNATION OF TEMPBEATURES. 3 



The works are designated by letters, the papers by Arabic numerals. The 

 former have no definite order, and no significance is to be attached to their 

 sequence. 



The papers are numbered, so far as possible, as in the " Catalogue of 

 Scientific Papers " published by the Royal Society of London (A), where 

 the order is intended to be chronological. The eight volumes of that 

 Catalogue already published include the papers which have appeared between 

 the years 1800 and 1873. On our list, the papers issued since the latter 

 date are assigned provisional numbers in italics. 



In the case of papers, as in the Eoyal Society Catalogue " when possible, 

 both the volume and the year have been given. With Transactions of 

 Societies the year to which the volume belongs, and not the year of 

 publication, has been given. A date enclosed in brackets marks the time 

 when a paper was read, which occasionally precedes by some years the date 

 of the volume in which it is printed." 



We shall be thankful for corrections or suggestions which may make the Bibliography 

 more extensive aud accurate. 



II.— THE DECIMAL SYSTEMS. 



§ 4. The two decimal systems used in scientific work are : — 



1. The measurement of Temperature upon the centigrade scale by the 

 thermometer of Celsius. 



2. The metric system of Weights and Measures. 



THE CENTIG-RADE THERMOMETER. 



§ 5. Upon this, the Thermometer of Celsius, (zero) represents the 

 temperature of melting ice. The point attained by the column of Mercury 

 at the temperature of boiling water is marked 100 {one hundred). 



Between these two points, the scale is divided into 100 degrees in groups 

 of 10 each. 



According to this scale, the average temperature of the human body is 

 between 37 and 38, and that of the comfortable atmosphere of a sitting- 

 room in winter about 20. 



Fahrenheit's Thermometer. — Upon this, the melting point of ice is 

 marked 32, and the boiling point of water 212. 



§ 6. Comparison and Reduction of the two Scales. — Since the 

 Fahrenheit thermometer is largely used in English-speaking countries, the 

 following Table and Formulae may be useful. The former is taken fi-oni 

 Littre et Robin, (A, 1594, Article " Thermometre ") ; the latter from 

 Dunglison, (A, 488, Article "Heat"). 



