Note :  is the prime following n in Lucas (4-23) an error?
 Howell WRONG -> Also - falls immediately from (4-19) with v = 0, 
        but then r - vt = r as well

  1. Start from precendents 
   04_19 E,B for symmetry point charge @v_const, add Faradays law to [Ampere]  

/$			∮[•d(l´),.over.L: (Ei´(r´,t´) - v/cBi(r´,t´)))  
			= - 1/c*     ∮[dAreap,.over.Ap: (∂[∂(t): Bi(r - v*t,t)]•n)
/*	re-base LHS of (4-19)
/$			∮[•d(l´),.over.L: (Ei´(r - v*t,t) - v/cBi(r - v*t,t)])  
			= - 1/c*     ∮[dAreap,.over.Ap: (∂[∂(t): Bi(r - v*t,t)]•n)
1)			∮[•d(l´),.over.L: (Ei´(r - v*t,t))
			= +     ∮[•d(l´),.over.L: v/cBi(r - v*t,t))  
			- 1/c*∮[dAreap,.over.Ap: (∂[∂(t): Bi(r - v*t,t)]•n)

/*	2. Howell application of Kelvin-Stokes to 1st term RHS
  Let Γ = lp, dS = da 
/$			∮ (•d(l´),.over.L :  v/cBi(r - v*t,t)) 
			= ∬[∂(Area): ∇(v/cBi(r - v*t,t)))  
/*	for RHS 
/$			∇(v/cBi(r - v*t,t)) 

a) Vector operations from Jackson1999 inside front cover
/$			∇(aβ) = a(∇β) - β(∇a) + (β∇)a - (a∇)β
 let a=v β=Bi(r - v*t,t)
			∇(v/cBi(r - v*t,t)) 
			= + v(∇Bi(r - v*t,t)) 
			  -		 Bi(r - v*t,t)*(∇v) 
			  +		(Bi(r - v*t,t)∇)*v 
			  - (v∇)β  
/*b) scalar triple products   Kreyszig1972 Section 5.9 p213-216
/$			β(c∂) = (β∂)c - (βc)∂  
 take β = ∇´, c = Bi(r - v*t,t), ∂ = v
				∇´		(Bi(r - v*t,t)v) 
			= + (∇´v)*Bi(r - v*t,t) 
			  - (∇´	 Bi(r - v*t,t))v 
 for constant v, ∇´v=∇´B=0, so 
c)			∇´(Bi(r - v*t,t)v) = 0 
/*  Using (c) in (1)
/$1)			  ∮[•d(l´),.over.L: (Ei´(r - v*t,t))
			= +     ∮[•d(l´),.over.L: v/cBi(r - v*t,t))  
			  - 1/c*∮[dAreap,.over.Ap: (∂[∂(t): Bi(r - v*t,t)]•n)

/*  Result 
/$			∮[•d(l´),.over.L: Ei´(r - v*t,t)) = - 1/c*∮[dAreap,.over.Ap: (∂[∂(t): Bi(r - v*t,t)]•n)

/*  key question is whether ?more rigorous? Jackson expression would yield 
   the same result as my simple Kreyszig application?
   (maybe check later - in (4-19) this seemed to be a problem?)
  04_21 convective derivative of Total magnetic flux density Bi  

/$			∂/∂(t)[Bi(r - v*t,t)] = ∂[∂(t): Bi(r - v*t,t)] + ∇´[Bi(r - v*t,t)v]   


/*++++++++++++++++++++++++++++++++++++++
/*add_eqn  "Re_check_later        
   04_23
   Faradays_Law_for_rest_circuit integral form E,B  

/$			∮[•d(l´): Ei(r - v*t,t)) = -1/c*∮[dAreap: ∂[∂(t): Bi(r - v*t,t)]•np) 
/%^%			∮[•d(l´): EIodv(POIo,t)) = -1/c*∮[dAreap,.over.Ap: ∂[∂(t): BIodv(POIo,t)]•R_A_PI2_odh)  

/*  OK - seems good, Note that this is for v=0, but how is this different than (4-2) Faradays Law? 
   some worry about vector formulae Jackson1999 versus Kreyszig1972  
   Note :  is the prime following n in Lucas04_23 an error?  
 where :  Rodh(Vonv_X_Rpcv(POIo)) is the unit normal vector at each point on area A