diff --git a/base/constants.jl b/base/constants.jl
index 6e29a837de84d..a7d5fdfdf3b25 100644
--- a/base/constants.jl
+++ b/base/constants.jl
@@ -2,7 +2,12 @@
 
 immutable MathConst{sym} <: Real end
 
-show{sym}(io::IO, x::MathConst{sym}) = print(io, "$sym = $(string(float(x))[1:15])...")
+function show{sym}(io::IO, x::MathConst{sym})
+    strx = string(float(x))
+    subs = strx[1:min(15,length(strx))]
+    dots = length(strx) >= length(subs) ? "..." : ""
+    print(io, "$sym = $subs", dots)
+end
 
 promote_rule{s}(::Type{MathConst{s}}, ::Type{Float32}) = Float32
 promote_rule{s,t}(::Type{MathConst{s}}, ::Type{MathConst{t}}) = Float64
@@ -86,7 +91,7 @@ macro math_const(sym, val, def)
     quote
         const $esym = MathConst{$qsym}()
         $bigconvert
-        Base.convert(::Type{Float64}, ::MathConst{$qsym}) = $val
+        Base.convert(::Type{Float64}, ::MathConst{$qsym}) = $(Float64(val))
         Base.convert(::Type{Float32}, ::MathConst{$qsym}) = $(Float32(val))
         @assert isa(big($esym), BigFloat)
         @assert Float64($esym) == Float64(big($esym))
@@ -98,6 +103,7 @@ big(x::MathConst) = convert(BigFloat,x)
 
 ## specific mathematical constants
 
+@math_const 💯        100                     BigFloat(100)
 @math_const π        3.14159265358979323846  pi
 @math_const e        2.71828182845904523536  exp(big(1))
 @math_const γ        0.57721566490153286061  euler