12 - Missing Formula by Mildred A Wirt Benson

15 - Missing Formula by Mildred A Wirt Benson

The Missing Formula is a thrilling young-adult mystery about orphan Anne Fairaday, who must uncover her father’s missing scientific formula before it falls into the wrong hands. With the help of her brave friend Madge Sterling, she embarks on a race against time filled with danger and deception.

14 - Missing Formula by Mildred A Wirt Benson

The Missing Formula is a thrilling young-adult mystery about orphan Anne Fairaday, who must uncover her father’s missing scientific formula before it falls into the wrong hands. With the help of her brave friend Madge Sterling, she embarks on a race against time filled with danger and deception.

13 - Missing Formula by Mildred A Wirt Benson

The Missing Formula is a thrilling young-adult mystery about orphan Anne Fairaday, who must uncover her father’s missing scientific formula before it falls into the wrong hands. With the help of her brave friend Madge Sterling, she embarks on a race against time filled with danger and deception.

12 - Missing Formula by Mildred A Wirt Benson

The Missing Formula is a thrilling young-adult mystery about orphan Anne Fairaday, who must uncover her father’s missing scientific formula before it falls into the wrong hands. With the help of her brave friend Madge Sterling, she embarks on a race against time filled with danger and deception.

11 - Missing Formula by Mildred A Wirt Benson

The Missing Formula is a thrilling young-adult mystery about orphan Anne Fairaday, who must uncover her father’s missing scientific formula before it falls into the wrong hands. With the help of her brave friend Madge Sterling, she embarks on a race against time filled with danger and deception.