THE REGISTER. 37 



of observation ; but before entering his records, he will carefully 

 examine them. To distinguish the observations made by his 

 substitute, he will enter them in red ink. 



As it is of the greatest importance that the series of observa- 

 tions should not be interrupted, and that there should be no 

 omissions, each observer will do well to instruct beforehand one 

 or more substitutes, who may be able upon occasion to take his 

 place. If, in spite of these precautions, the observation has ne- 

 cessarily been omitted, its place will be left blank in the journal. 

 In this case the observer must never fill up these blanks with 

 calculations, according to his judgment; he should consider the 

 conscientious observance of this rule indispensable to truth and 

 good faith. He should remember, besides, that if he acts dif- 

 ferently, he not only lessens the value of these results, but brings 

 into doubt and disfavor the fidelity of his other observations, and 

 takes from them what constitutes their greatest value for science 

 confidence. 



THE REGISTER. 



In the register the first page is devoted to regular observations; 

 the second to additional observations, to periodical or extraor- 

 dinary phenomena, and to monthly recapitulations. The head- 

 ings of the columns indicate clearly the use of each. 



For each instrument the columns follow each other in the order 

 in which the observations are to be made, and one column is re- 

 served to enter the observation just as it is made, and before any 

 correction or reduction. As each sheet is to be regarded as an 

 independent document, it should carry with it all that is neces- 

 sary to correct the observations therein contained, and to render 

 them authentic. Thus, the date of the year, the month, the 

 precise locality, the latitude and longitude, the elevation of the 

 instruments from the ground and above the sea, the nature and 

 condition of the instruments which have been employed, and the 

 amount of their corrections; finally, the signature of the observer 

 should be repeated on every leaf. It will be sufficient, for this, 

 to fill the blank spaces left after the different printed titles in the 

 blank forms. The observer should the less neglect this important 

 duty, as it is an affair of only a few strokes of the pen each 



