144 



IT. S. COAST AND GEODETIC SURVEY. 



checked before proceding with the analysis. Large errors can usually 

 be detected by plotting the means. 



Form 21^.1)., commutation of {Y^-^ u) (fig. 27) . — This form provides for 

 the computation of the equilibrium arguments for the beginning of 



Tabulated by . 



Summed by . 



Fig. 23. 



the series of observations, the computation being in accordance with 

 formulas given in Table 3. For the most part the form is self- 

 explanatory. The values of the mean longitude of the moon (s), of 

 the lunar perigee (p), of the sun (h), of the solar perigee (pj), and of 

 the moon's ascending node (N), may be obtained from Table 4 for 



