Most of the book is just as relevant today as when he first published it in 1930. The methodology of genealogical research and analysis hasn't really changed all that much. Although a wide variety of resources, instantly available at our fingertips online, have made research easier and more accessible today, the principles remain the same.
Only two sections of the book seem antiquated from today's vantage point. One is a rather quaint discussion of writing family history aimed for publication.1 Publishing has undergone such a radical transformation in the last few years that books about it from just ten years ago are obsolete and seem ancient today. Now, anyone with an internet connection could write and publish a professional-looking book from home, printed on-demand by one of several publishing firms.
The other is his chapter on Genealogy and Eugenics.2 As historians, we must remain disinterested in the subject at hand. If we're reading the book as history (both as a source of primary information about genealogical practices of the period, and secondary information on the sources and case studies included), we must remember the view he represents was widely accepted at the time. Recall the infamous statement of otherwise revered supreme court justice, Oliver Wendell Holmes: "Three generations of imbeciles are enough."3 However, it's difficult to stay objective with repulsive paragraphs like this:
By learning how nature works, and by utilizing human reason in the deliberate application of natural laws, the process of elimination of the unfit can be hastened, and needless suffering reduced to a minimum. Experience with plant and animal breeding proves that the program of eugenics is definitely within the realm of the possible. The kindest way to eliminate the unfit, and thus raise the average of human efficiency, is to prevent the reproduction of the unfit when the family history clearly indicates that most of the progeny are almost certain to be defective.4It wasn't until the horrors of the Nazi regime were uncovered, which had taken both positive and negative eugenics to their logical conclusion, that this pseudo-scientific movement began to lose support. Unfortunately, its application didn't end right away in America. That the chapter was even included in the 1968 edition shows the movement still existed–indeed, there are still remnants in contemporary society. Other places in the book have minor updates or added explanatory notes, but there are none in this chapter. Let its continued inclusion serve as a grim reminder and warning.
On a lighter note, there's much in the book still useful for the beginning or intermediate genealogist. As a specialist in New England research, the case studies and sources he discusses are mostly from that area. I've only recently begun seriously researching my colonial ancestors, so many of the examples he used were new to me, or revealing about information I've already found.
To summarize his advice on the use of published family histories: don't take them at face value. There might be lots of useful data, but it's important to have a critical eye. They're likely to be most accurate for a couple generations prior to those living at the time it was written. He even mentioned a specific work I'd already found on some of my ancestors. What Jacobus calls a "magnificent history of the Henry Whitney family" nonetheless included a falsified pedigree of the progenitor from another source, uncritically accepted as fact.5 (I already knew the purported English ancestry in the book was based on a fraudulent genealogy, but only because I read the front matter.6 There aren't any notes within the text itself to alert readers of this fact.)
Not only does the book offer good advice on research, analysis, and writing, but it's an enjoyable read. I particularly liked this humorous explanation for why ages in the census can often be wrong:
Do not feel upset if inconsistencies or errors are occasionally encountered. If you obtain a listing of the family in both 1850 and 1860, you may find that your granny's age increased less than ten years during the decade, for that is a woman's privilege.7Aside from one minor, but not insignificant flaw, this book is still a valuable resource. I didn't even touch on many of the subjects covered by the book. Besides the aforementioned topics, there are useful sections on Puritan society, naming practices, royalty, the profession of genealogy, more on using sources, estimating the number of descendants, and a good explanation of the switch to the Gregorian calendar. It's only 120 pages long, divided into bite-size chapters, so it can easily be read in a weekend. I think I could get even more utility out of the book, so I'm going to buy a copy to keep on my shelf.
1. Donald Lines Jacobus, Genealogy as Pastime and Profession, 2nd edition (Baltimore: Genealogical Publishing, 1968), 93-95.
2. Jacobus, 102-105.
3. Buck v. Bell, 274 US 200 (1927), FindLaw (http://laws.findlaw.com/us/274/200.html : accessed 31 May 2011).
4. Jacobus, 104.
5. Jacobus, 37.
6. S. Whitney Phoenix, The Whitney Family of Connecticut, and its Affiliations; Being an Attempt to Trace the Descendants, as Well in the Female as the Male Lines, of Henry Whitney, from 1649 to 1878; to Which is Prefixed Some Account of the Whitneys of England (New York: privately printed, 1878), handwritten insert at the beginning of the book; online database, Ancestry.com (http://search.ancestry.com/search/db.aspx?dbid=27285 : accessed 31 May 2011), images 0_5 and 0_6.
7. Jacobus, 115.