How can candy be so complicated?

I just finished reading a book reprint from the Cornell University Library titled "Home Candy Making" with a date of 1889.  However, on page 8, it says to not store candy in the refrigerator.  A refrigerator . . . in 1889?  I had to investigate.

The history of the refrigerator is about as stable as radioactive uranium.  Depending on what website I view, refrigerators in homes existed as early as the 1830s or as late as the 1910s.  Since I could not pin that down, I went out to check on when electricity was available in homes.  The general consensus is homes did not have electricity until about the 1890s.  Another website says the refrigerator "as we know it now" did not come into existence until the 20th century, although the word refrigerator was coined in 1805.

Since the author of this book is identified as the principal of the Philadelphia Cooking School, it is possible she had access to refrigerators before most homes would have had them, as refrigeration in breweries and railroad card goes back to the 1840s.  (The refrigerator coil was actually invented in the 11th century by a Muslim scientist to aid in distillation of essential oils.)

I am now not sure if I should rely on this book as authentic.  I hope I can, because it contains some other interesting facts:  Candies were made "marble" size, candies were not dipped in chocolate, there were no thermometers used, and all colorings were homemade.  So, do I believe the Cornell University Library or put this book aside?