1 \documentclass{amsart}

     2 

     3 \usepackage{tikz}

     4 \pgfrealjobname{tikz-figures}

     5 

     6 \begin{document}

     7 

     8 \begin{figure}

     9 \centering

    10 \beginpgfgraphicnamed{figure1}%

    11 \begin{tikzpicture}[%every label/.style={green}

    12 ]

    13 \node[fill=black, circle, label=below:$E$, inner sep=1.5pt](S) at (0,0) {};

    14 \node[fill=black, circle, label=above:$E$, inner sep=1.5pt](N) at (0,2) {};

    15 \draw (S) arc  (-90:90:1);

    16 \draw (N) arc  (90:270:1);

    17 \node[left] at (-1,1) {$B_1$};

    18 \node[right] at (1,1) {$B_2$};

    19 \end{tikzpicture}

    20 \endpgfgraphicnamed%

    21 \mbox{} % <-- weird, doesn't compile unless I put something here after the \endpgfgraphicnamed...? -S

    22 \caption{Combining two balls to get a full boundary.}\label{blah3}\end{figure}

    23 

    24 \begin{figure}

    25 \centering

    26 \beginpgfgraphicnamed{figure2}%

    27 \begin{tikzpicture}[%every label/.style={green},

    28 				x=1.5cm,y=1.5cm]

    29 \node[fill=black, circle, label=below:$E$, inner sep=2pt](S) at (0,0) {};

    30 \node[fill=black, circle, label=above:$E$, inner sep=2pt](N) at (0,2) {};

    31 \draw (S) arc  (-90:90:1);

    32 \draw (N) arc  (90:270:1);

    33 \draw (N) -- (S);

    34 \node[left] at (-1/4,1) {$B_1$};

    35 \node[right] at (1/4,1) {$B_2$};

    36 \node at (1/6,3/2)  {$Y$};

    37 \end{tikzpicture}

    38 \endpgfgraphicnamed%

    39 \mbox{} % <-- weird, doesn't compile unless I put something here after the \endpgfgraphicnamed...? -S

    40 \caption{From two balls to one ball.}\label{blah5}\end{figure}

    41 

    42 

    43 \end{document}

    44