“Nervous as a long-tailed cat in a room full of rocking chairs”

“Nervous as a long-tailed cat in a room full of rocking chairs” means to be very nervous—the cat must not get the tail caught under a rocking chair. The syndicated newspaper column “Senator Soaper Says” was started by Harry Vincent Wade (1894-1973) of the Detroit (MI) News, who was then followed by William E. (“Bill”) Vaughan (1915-1977) in 1953; “Senator Soaper” wrote in September 1953:
 
“Next to living on the side of a volcano, the most hazardous existence we can think of is that of a long-tailed cat in a house full of rocking chairs.”
 
The recording artist and television host Tennessee Ernie Ford (1919-1991) said in 1956, “He was nervous as a long-tailed cat in a roomful of rocking chairs.” The expression is still popular in Texas and other Southern states.
 
 
Wiktionary: nervous as a long-tailed cat in a room full of rocking chairs
Etymology
More elaborate form of nervous as a cat. Implication is that cat is afraid of its long tail being pinched by a rocking chair.
Adjective
nervous as a long-tailed cat in a room full of rocking chairs
1.(simile) Extremely nervous.
 
Wikipedia: William E. Vaughan
William E. (“Bill”) Vaughan (October 8, 1915 – February 25, 1977) was an American columnist and author. Born in Saint Louis, Missouri, he wrote a syndicated column for the Kansas City Star from 1946 until his death in 1977. He was published in Reader’s Digest and Better Homes and Gardens under the pseudonym Burton Hillis. He attended Washington University in St. Louis.
 
His folksy aphorisms (published in his “Starbeams” feature) are often collected in books and on Internet sites.
   
30 September 1953, The Oregonian (Portland, OR), “Senator Soaper Says,” pg. 3M, col. 2:
Next to living on the side of a volcano, the most hazardous existence we can think of is that of a long-tailed cat in a house full of rocking chairs.
 
Google News Archive
30 June 1954, Waycross (GA) Journal-Herald, “Game and Fish” by Joe Stearns, pg. P7, col. 4:
My own bass lure invention has made me about as happy as a long tailed cat in a house full of rocking chairs.
 
29 March 1956, Bradford (PA) Era, pg. 1, col. 1:
AND WE QUOTE: From a recent Industrial Press Service release, we liked these:
(...)
“He was nervous as a long-tailed cat in a roomful of rocking chairs.”—Tennessee Ernie.
 
29 April 1956, Dallas (TX) Morning News, “Weather Vane,” pt. 4, pg. 1, col. 1:
Simile for an officer-seeker who is unopposed as the filing deadline approaches on May 7: As nervous as a long-tailed cat in a roomful of rocking chairs. 
 
5 July 1956, San Diego (CA) Union, “Point of View” by Donald Freeman, pg. A16, col. 1:
It’s Tennessee Ernie’s simile: “As nervous as a long-tailed cat in a room full of rocking chairs!”
 
27 January 1958, Milwaukee (WI) Journal, “Caesar Show Is Just So-So” by Don Dornbrook, pt. 2, pg. 6, col. 6:
After an eight month lay-off, Caesar had a lean and hungry look. He was also, as Tennessee Ernie Ford would say, “as nervous as a long tailed cat in a roomful of rocking chairs.”
 
Google Books
How to Speak and Write with Humor
By Percy H. Whiting
New York, NY: McGraw-Hill
1959
Pg. 102:
For example: “like a cat in a room full of scratching posts,” “like two kids with their bellies full of green apples,” and “like a long-tailed cat in a room full of rocking chairs.”