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or any gradation upward from the simpler to the more

difficult parts.

This defect has been greatly minimized by numbering each paragraph and to keep them sufficiently pointed to differ from the preceding or succeeding ones. Throughout the work wherever the necessity occurs, reference by number will be made to such paragraphs in other parts of the book; this will make the subject matter more easily understood without the necessity of repeating; saving much space. Thus operations which are common to many branches of painting are only described once and the reader will be referred by number to where the additional information can be found. This it is hoped will reduce the defect mentioned above to its lowest limits.

Besides a very copious index has been prepared which will enable the reader to find readily every phase of any subject treated.

To enable students to memorize or recollect the subject matter of each heading, a series of questions will be found at the end numbered to correspond to that of the paragraphs containing the answer. This will enable the student to determine for himself the correctness of his own answer.

As many persons no doubt will buy this book with a view to educating themselves upon one branches of the trade-in a manner it will take the place of the correspondence school to such-at a greatly reduced cost.

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In organized, practical trade schools, it is hoped that it may prove a valuable help, not only to the students but also the instructors—in that under classified headings any or at least most of the subject matter relating to the branches taught will be found treated and the questions which are added at the end of each heading will permit its use as a text book in such schools.

It makes no claim to be able to lead the student along as fast nor as well as he would under the personal surveillance and advice of a capable instructor who can demonstrate an error in a practical way—but where it is used as an adjunct to his oral instruction and as a book of reference by the student, it will greatly facilitate the acquiring of knowledge.

The lack of such a book for the purpose indicated above, is one of the main reasons for its publicationaside from the need of a manual covering the ground and subject matter treated in a late and up-to-date manner.

Again it is repeated that many branches of painting require appliances, tools, colors, etc. To save repetition, each of these are treated fully but once, under their several headings, and if the reader will care to inform himself more fully in regard to any of these, he can readily do so by referring to the paragraph number indicated as describing such.

With the above synopsis of the scope and manner of handling the subject matter of the book, it is presented to the world—not as the acme of perfection, which unfortunately is unattainable, but as a helping hand to the student or others seeking general information on the paint and kindred trades—with the hope that many may be benefitted by its perusal, study, or use as a reference book.

F. MAIRE.

MODERN PAINTER'S CYCLOPEDIA

ADULTERATION

1. There is much less need of an extensive knowl-
edge of the “how to detect” adulteration in painting
material today than was necessary only a decade ago.
Thanks to the wise action of the general government
and that of many of our state legislatures, the gross
adulterations to which all such material had been sub-
jected then, has been greatly curtailed since. At the
present time it is possible for one to know to a cer-
tainty the composition of any color, or what are the
contents of any barrel, can or other package containing
paint, varnishes, vehicles, etc. The law in many of our
states forcing the manufacturer to state upon the label
the name of every ingredient entering into the compo-
sition of the contents. So if the name of a desired color,
say Chrome yellow, medium, is printed upon the label
as pure, and the name of the manufacturer appears
upon it too, one may be safe in buying it for what it is.
The greatest danger is in the buying so-called second
quality goods. In the above instance suppose the label
said “Chrome yellow-medium. Contents, chrome yel-
low and barytes. Of course this indicates that it is not
pure—but how much pure? It may contain 25% pure

2.

chrome yellow and 75% barytes which is about the average in the better grade of off colors, or it may be 10% chrome yellow, and even much less, and the rest barytes. And in the dry colors many run as low as 3% actual colors to 97% barytes chalk or other adulterants.

In colors or pigments dry or ground in oil, water or japan, there is a possibility of greatly adulterating most of these without any remarkable change in the looks of the goods themselves, so that it requires a knowledge of the principal ingredients used in adulterating to understand how to detect them.

3. Heavy weight colors are usually adulterated with some substance of as near the bulk or weight as their own; besides the adulterant must be as clear or colorless as possible, so as not to change materially the color or tone of the pigments they are added to. If much lighter in weight the usual size package used to pack the pure color would have to be greatly increased to accommodate the larger bulk of the adulterant needed to make up the weight. This would at once give it away in the mind of one who is at all familiar with the customary packaging of pure goods.

4. What is known as Barytes or Barium Sulphate is the most common adulterant used in the sophistification of all heavy colors. This substance seems eminently well fitted for this purpose as when mixed in oil it is so very transparent that it may be painted over new wood in several coats without hiding the grain of the wood much more than so many oilings would have

a.

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