Thanks for your help.  I'm glad I was able to let you know about wget2.  
Searching for wget in Muon also shows pwget which is described as a 
downloader utility which resembles wget but implemented in perl.    Also 
python-3-wget.

/wget 
--ca-certificate=/etc/ssl/certs/USERTrust_RSA_Certification_Authority.pem 
wget https://www.gutenberg.org/ebooks/68992.epub.images worked. /There 
has to be some way to tell wget where the certificate file is without 
having to use the  --ca-certificate option. That's my next project.  
Thanks to everyone for your help.