How to become a lightning calculator

  7   4
In Category - Arithmetic
Anonymous Project Gutenberg 2021
Mental arithmetic Readers of public-domain and historical texts
Project Gutenberg digital edition en

Edition facts

Words: 5,799
Reading time: 26 min
Text sections: 17
A concise 1894 manual promising rapid mental arithmetic through methods like adding two columns at once and a short interest rule, with a pragmatic tone and embedded advertising.
Share

This 1894 pamphlet, issued as the second number of the Multum in Parvo Library, advertises itself as the “Smallest Magazine in the World.” Its anonymous author wastes no space: the first rule, “Accuracy should be first considered, then rapidity,” is immediately undercut by the claim that “quick adders, by the way, are the most accurate.” That tension between caution and speed runs through every page. The book teaches techniques such as adding two columns at once, a “short method” for interest, and a proof of multiplication that takes “ten seconds.” It also plugs a separate volume, W. D. Rowland’s How to become expert with figures, and includes a “Mail Directory” that promises to flood the reader with free samples and catalogues.

Speed Before Accuracy?

The manual opens with a paradox: “Accuracy should be first considered, then rapidity.” Yet the very next sentence declares that “quick adders, by the way, are the most accurate.” This contradiction is never resolved; instead, the text proceeds to advocate for methods that prioritize speed. For example, it advises the reader to “keep your thought on results not numbers themselves” and to avoid saying “7 and 4 are 11 and 8 are 19” but instead “say 7, 11, 19 and so on.” The goal is to eliminate intermediate mental steps. Similarly, when adding horizontally, the instruction is to “begin at the left,” a reversal of the usual right-to-left approach. The author seems less concerned with theoretical correctness than with practical efficiency, even if that means bending conventional wisdom.

The Arithmetic of Commerce

The examples and problems in this pamphlet are overwhelmingly financial. The section on “Interest Computations” walks through calculating interest on $462.50 for one month and eighteen days at 6 percent, using a method that divides 360 (the “interest year”) by the interest rate. Other sections cover “Bank Discount,” “Equation of Payments,” and “The Canadian Interest Rule.” The emphasis is on the kind of arithmetic a clerk or merchant would perform daily. The author even includes a “Table of Transposed Numbers,” presumably to help catch errors in ledger entries. This focus on commerce is reinforced by the promotional material: the book itself is a product sold by subscription, and it offers readers a chance to have their names added to a “Mail Directory” for two years, ensuring a stream of commercial circulars.

A Self-Promoting Format

The pamphlet’s structure blurs the line between instruction and advertisement. The title page identifies it as “Vol. I. February, 1894. Published Monthly. No. 2,” and the subscription price is 50 cents per year. Within the text, the author recommends Rowland’s book and provides ordering instructions: “You can get this handy book by sending 25 cents in stamps to American Nation Co., Boston.” The final pages include a “Mail Directory” that explains how readers will receive “sample copies of publications, circulars, catalogues, etc.” from various concerns. This commercial framing suggests that the manual’s primary purpose may have been to generate leads and sales rather than purely to educate. The reader is both student and potential customer.

Readers should approach this pamphlet as a period artifact as much as a practical guide. The methods are presented without proof or derivation, and the author’s claims about speed and accuracy are asserted rather than demonstrated. The value lies in observing how arithmetic was taught to a popular audience in the 1890s—and how that instruction was embedded in a commercial enterprise. For those interested in historical pedagogy or the self-improvement literature of the Gilded Age, this slim volume offers a revealing snapshot.

Related eBooks