Pictured below are three pages from my great-grandfather’s original 1871 diary, which; along with the signature photo and Jesse James family photo, are now part of my copyrighted (C) Betty Dorsett Duke Collection. Jesse James signed his diary “J. James” and “James L. Courtney”. Jesse W. James was his real name and James L. Courtney was his alias.
He wrote the entire diary in pencil, just as he did in a six page letter he wrote to Dr. Reuben Samuel, his step-father. I wasn’t aware of this letter until Michigander, Matt Hamlin, sent the following link to me:
http://www.christies.com/lotfinder/lot_details.aspx?intObjectID=4467782
The letter, along with its complete transcription, may also be viewed at this site:
http://forums.delphiforums.com/Zeke1/messages?msg=926.13
Both Jesse James and Dr. Reuben Samuel are pictured in the eBay photo of the James and Jackson families (with friends)

Matt Hamlin pointed out that the T’s in both samples are identical. The same applies for some of the other letters of the alphabet. While reading his diary I noticed that he sometimes made his J’s fancy like this:

And other times he made his J’s plain – like he did in his signature on the Christie’s letter pictured on the right below. The slant, writing style, and spelling is also the same in both handwriting samples.

Transcription follows:
June 1871
28 Wensday for book .50
for wagon grease .25
29 Thirsday morning
for milk .25
at Decatur in camp back of the tin shop and remained there all day and in the evening went ahunting with H Pratt and Edward Sunderland and the tavern keep, and I killed a deer.
30 Friday morning in camp back of the tin shop and rized up for to start south
for corn 1/2 lb .75
for caps for gun .75”

Transcription follows:
“James L. Courtney
his book bought June 28/ 1871
at Decatur Texas price 50 cts
if the oner should be found ded his uncle lives in cass co mo. his address is as folows E. L. Andrass Brosley po cass co mo if the oner should be found dead the person he [maybe who?] finds this will please rite immediately to E. L. Andruss Brosley po cass co mo”

The same last page of the letter signed Jesse W. James letter (auctioned by Christie’s) is pictured again top right for comparison purposes. Another excerpt from a letter signed Jesse W. James is pictured on the right below. Compare the way Jesse James AKA James L. Courtney wrote the word “to”, (the first word in the third line from the top), is almost exactly like he wrote it in the letter. Also check out the W’s, H’s, and T’s. There are examples of my great-grandfather underlining words on other pages of his diary:
Transcription of letter on bottom right:
“do & if we were free men we would do all in our power to put it down [illegible] Allen of Liberty made similar remarks about us to [illegible] [illegible] a few days ago to but he will probably regret it. if you value your life you had better retract your slander” Jesse W. James”
Transcription of the diary page pictured top left above:
“W. M. Roberts branded on the left hip B to [two?] marks [?] [illegible] [illegible] to under half crop and the other under cut [?] in the rite & and [illegible] half crop in the left. John Hitson & Bill [John & Bill Hittson] Palapinto co & Teresa [?]”
For more information on E. L. Andruss and a robbery attributed to the James Gang in Coldwater, Brosley County, Missouri click on the following links:
http://forums.delphiforums.com/Zeke1/messages?msg=926.26 http://forums.delphiforums.com/Zeke1/messages?msg=926.24
More information about the Brosley, Cass Co., MO robberies – courtesy of Daniel Duke. National Republican article: http://chroniclingamerica.loc.gov/lccn/sn86053573/1873-12-12/ed-1/seq-1/;words=county+Cass+Missouri?date1=1873&rows=20&searchType=basic&state=&date2=1873&proxtext=cass+county+missouri&y=15&x=15&dateFilterType=yearRange&index=1 The State Journal article (Jefferson City, MO): http://chroniclingamerica.loc.gov/lccn/sn87052128/1873-12-12/ed-1/seq-2/;words=county+Cass+Missouri?date1=1873&rows=20&searchType=basic&state=&date2=1873&proxtext=cass+county+missouri&y=15&x=15&dateFilterType=yearRange&index=2