PLANK MEASURE (Concluded).

CONTENTS OF PLANKS IN BOARD MEASURE. THICKNESS, 34

ft. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. feet. 31 54 63 72 81 99 109 118 127 136 145 154 163 172 181 103 112 121 131 140 149 159 168 177 187 106 116 125 135 144 154 164 173 183193 99 109 119 129 139 149 159 169 179 188 198 92 102 112 123 133 143 153 163 174 184 194 204

90

32 56 65 75

84

93

33 58 67

77

87

96

34 59 69

79

89

35 61 71

82

NAILING MEMORANDA.

[From "Builder's Guide, and Estimator's Price-Book."]

Quantity of Nails for Different Kinds of Work.

1000 covering boards.

RELATIVE HOLDING POWER OF WIRE AND CUT NAILS.

Tests made by a committee appointed by the Wheeling Nail Manufacturers.

This test showed the relative value of a pound of each kind to be as follows:

1 lb. of 20d. cut nails equals 1.40 lbs. of wire nails.

In obtaining the above results, two tests were made of the 8d. cut nails, and four of the 8d. wire nails; three tests each were made of the 6d. and 4d. cut nails, and 6d. and 4d. wire nails, and the average is shown.

The committee report as the result of their experiments that $1.00 of cut nails will give the same service as $1.78 in wire nails, if at the same price per pound.

Very thorough tests of the comparative holding power of wire nails and cut nails of equal lengths and weights were made at the United States arsenal, Watertown, Mass., in November and December, 1892, and January, 1893. Fifty-eight series of tests were made, each series comprising ten pairs cut nails and wire nails, making a total of 1,160 nails tested. From forty series, comprising forty sizes of nails driven in spruce wood, it was found that the cut nails showed an average superiority of 60.50 per cent.; the common nails showing an average superiority of 47.51 per cent., and the finishing nails an average of 72.22 per cent.

In eighteen series, comprising six sizes of box nails driven into

pine wood, in three ways the cut nails showed an average superiority of 99.93 per cent.

In no series of tests did the wire nails hold as much as the cut nails.

MEMORANDA FOR PLASTERERS.

Measuring Plasterers' Work.

The following paragraphs, taken from one of our leading jour nals, describe the usual method of measuring plasterers' work :— “Plastering is always measured by the square yard for all plain work, by the superficial foot for all cornices of plain members, and by the linear foot for enriched or carved mouldings in cornices.

“By ‘plain work' is meant straight surfaces (like ordinary walls and ceilings), without regard to the style or quality of finish put upon the job. Any panelled work, whether on walls or ceilings, run with a mould, would be rated by the foot superficial.

"Different methods of valuing plastering find favor in different portions of the country. The following general rules are believed to be equitable and just to all parties:

66

First, Measure on all walls and ceilings the surface actually plastered, without deducting any grounds or any openings of less extent than seven superficial yards.

"Second, Returns of chimney-breasts, pilasters, and all strips of plastering less than twelve inches in width, measure as twelve inches wide; and where the plastering is finished down to the base, surbase, or wainscoting, add six inches to height of walls.

"Third, In closets, add one-half to the measurement. Raking ceilings, and soffits of stairs, add one-half to the measurement; circular or elliptical work, charge two prices; domes or groined ceilings, three prices.

"Fourth, For each twelve feet of interior work done farther from the ground than the first twelve feet, add five per cent; for outside work, add one per cent for each foot that the work is done above the first twelve feet.

"Stucco-work is generally governed by the following rules; viz., mouldings less than one foot girt are rated as one foot, over one foot, to be taken superficial. When work requires two moul is to run same cornice, add one-fifth. For each internal angle or mitre, add one foot to length of cornice, an 1, for each external angle, add two feet. All small sections of cornice less than twelve inches long measure as twelve inches. For raking cornices, add one-half; circular or elliptical work, double price; domes and groins, three prices.

For enrichments of all kinds a special price must be

charged. The higher the work is above ground, the higher the charge must be; add to the rate of five per cent for every twelve feet above the first twelve feet."

Useful Memoranda.

The average yield of lime paste from the best Eastern limes has been found to be 2.62 times the bulk of the unslaked lime. A barrel of good quality, well-burnt lime should make eight cubic feet of lime paste.

Careful experiments, conducted by United States engineers, have demonstrated that the average sum of voids in sharp, clean, silicious bank or pit sand, thoroughly screened, is .349 of its bulk, and that the best mortar is obtained by mixing with the sand such an amount of lime paste as will be from forty-five to fifty per cent. greater than the amount needed to fill the voids of the sand, or, in other words, by mixing one part lime paste to two of sand.

To each barrel, or each 200 pounds of unslaked lime, one and a half bushels of good quality, long cattle hair, well whipped and washed, should be used in the first coat on lath work, and a half bushel of hair to each barrel of lime in the brown coat, whether applied over a scratch coat or on brick, iron, or terra cotta.

The lime should be slaked not less than two weeks before the plaster is applied to the walls, and the hair should be mixed in just before using. If the hair is mixed into the mortar while the lime is hot, the lime will burn and rot the hair.

Sand for mortar should be angular, not too coarse or too fine, and should be free from all foreign substances, and particularly fine loam or clay. Clean river or pit sand, carefully screened, is generally considered the best for mortar.

Hair, such as is used by plasterers, is obtained from the hides of cattle, and is put up in paper bags, each bag being supposed to contain one bushel of hair when beat up. The quantity of hair to be used is sometimes designated by weight, but as it is sold by the bushel or bale, that appears to be the better measure.

Plastering on lath work is generally done in three coats. The first coat is called the scratch coat, and is generally made very "rich." The second coat is called the brown coat, and usually contains a much larger proportion of sand and only a small quantity of hair. On brick and stone walls the scratch coat is generally omitted, and the brown coat is applied directly to the brick or stone work, and of the proper thickness to receive the finish coat.

The third, or finishing, coat is designated by various terms, such as skim coat, white coat, putty coat, sand-finish, etc. The skim coat as used in the Eastern States is generally composed of lime putty and washed beach sand in equal proportions. Sand-finish, which has a rough surface resembling coarse sandpaper, is mixed in the same way, only the coarser sand and more of it is used, and it is finished with a wooden or cork-faced float.

White coating, or hard finish, generally means a composition of lime putty, plaster of Paris, and marble dust. Plaster of Paris and marble dust when used should not be mixed with the lime putty until a few moments before using, and no more should be prepared at one time than can be used up at once, as it soon "sets," after which it should not be used. The skim coat, or hard finish, should be finished with a steel trowel and wet brush.

the work is trowelled the harder it becomes.

The more

To obtain the best quality of lime plaster, the specifications should read as follows:

"The mortar for plastering to be composed of best quality wood-burned stone lime, white, slaked at least fourteen days before using, and run through a fine sieve, and to be thoroughly mixed with clean, sharp sand, free from clay, loam, or other foreign substances, in the proportion of one-third lime paste to twothirds sand, measure for measure, to be well tempered, and have the best quality of clean, long cattle hair, well wetted, thoroughly mixed with it immediately before using, as follows:

"First coat for lath work, 14 bushels of hair to one barrel of unslaked lime; first coat for brick and terra-cotta work, and second coat for lath work, onehalf bushel of hair to one barrel of unslaked lime. First coat to be put on strong, brought to a fair surface and scratched; the second coat to be put on light and well floated with long rules to a uniform surface, straight and true; each coat to be thoroughly dry before the next is put on."

In the West 200 pounds of unslaked lime is considered the equivalent of a barrel. Rockland (Me.) lime will average 220 pounds to the barrel.

Very little plaster is mixed by measure, however, the usual custom being to mix in as much sand with the slaked lime as the mortar-mixer thinks is best, or that the plaster will stand and work well. Plaster mixed in the proportions specified above will require about 2 casks or 500 pounds of lime, 45 cubic feet or 15 casks of sand, and 4 bushels of hair, to cover 100 yards of lath work with mortar of an inch thick.

For the white coat, allow 90 pounds of lime, 50 pounds of plaster of Paris, and 50 pounds of marble dust to 100 square yards.

To lath the same area will require from 1,400 to 1,500 laths, and 0 pounds of 3d, nails.