116 GIUSEPPE GOBI 



8. Forinole differenziali. — Le forinole 



dB 



V l—é> 



\—rt 



V\+l 



} 1 — m 2 



l_ e 2 sin 2B " i+2wcos2B + «* ' l+8cos*B 1+»mcos2B 

 per B=38°6'44",0, latitudine geografica dell'antico Circolo di Ramsden, danno 



^ = [9,9985458.2023— 10— 9,9988943.8353+ 10]=[9,9996514,3670 — 10] 

 dB 



=[9,9999987.8271—10—0,0003473.4602] =[9,9996514.3669-10] 

 =[0,0014541.7977—10—0,0018027.4307] =[9,9996514.3670-10] 

 =[9,9999975.6544—10—0,0003461.2874] =[9,9996514.3670—10]. 



Le forinole : 



dg 1— fi 2 cos 2 p 1— 2»cos2p+H« 1+Ssin 2 |3 1— m cos 2j3 



dB' 



V I—e 2 



l-'lH-S Vl—m* 



per (3=38°r 8/7415055, latitudine ridotta dell'antico Circolo di Ramsden, danno: 



^-=[9,99S1972.5692— 10— 9,9985458.2023 -f 10=[9.9996514.3669— 101 

 dB 



=[9,9996502.1941— 10— 9,9999987.8271 +10]=[9,9996514.3670— 10] 

 = [0,0011056.1647—0,0014541.7977] =[9.9996514.3670—10] 



=[9,9996490.0213— 10— 9,9999975.6544 + 10]=[9,9996514.3669— 10]. 



In ogni caso si ha 



Le forinole 



dB' \—é 



d^ 

 dB 1 



=0,9991977253. 



(1-rc 2 ) 2 



1+& 



f/B 1— (2e 2 — e 4 ) sin 2 B 1+6w 2 +« 4 +4m(1+w 2 )cos2B 1+(2&-|-S 2 )cos 2 B" 



1— m 2 



l-t-2m cos 2B+»2 2 



per B=38"6'44",0, danno 

 dB 



dB 



= [9,9970916.4046— 10— 9,9977933.5274+10]=[0,9992982.8772— 10] 



=[9,9999975.6542—10—0,0006992.7772] =[9,9992982.8770—10] 

 =[0,0029083.5954—0,0036100.7182] =[0,9992982.8772—10] 



=[9.9999951.3087—10—0,0006968.4316] =[9,9992982.8771—10]. 



