2 Stromeyer, Projection on a Conical Mantle. 



A 



to LiC and MN is normal to LiD, therefore the angle 

 LiNM = CLiD, and therefore the two triangles are similar. 



Li M ^ CD 

 •'• LiN~CL,' 



From the pairs of similar triangles CAD, LiAF and 

 CAB, LjAH, we find 



CD AC 

 LiF'AL,' 



^ CB AC 



and -, — ^ = XT — 

 I.2H A 1-0 



But CB = CLi being radii of a sphere, and ALi = AL2 

 being radii of a sphere. Substituting the values for CD 

 and CLi, we have 



LiM AC.L,F AL, _ L,F 

 L,N~ AL, ■ UH.AC L,H 



