structed in all its parts of material same as used in the large Hunt gun already approved by this board.

The board, under the authority conferred upon them by section. 4429, Revised Statutes, approved the following coil and pipe boilers, when constructed in all their parts of wrought iron or steel plates: Henry Sutter, Griswold Pipe Generator and the Sutter Sectional Porcupine boiler; Louis S. Clark, Pittsburg, Pa.; H. H. Frederick, New Orleans (3-horse power); E. A. Magee, Brooklyn, N. Y.; A. E. Corey, Allegheny, Pa.; Stillman Saunders, Providence, R. I.; Wickes Bros., East Saginaw, Mich.; Augustus Bailey, Spuyten Duyvil, N. Y.; Thomas Fearon, Yonkers, N. Y.; Howard Steam Generator, H. J. Hancock, New York, N. Y.; Coller Sectional Boiler, Coller Yacht and Engine Works, Detroit, Mich.; Taylor Bros., Trenton, N. J.; Seachrist & Parker, Erie, Pa.; Laughlen & Co., Pittsburg, Pa.; B. Louis Toquet, Westport, Conn.; Warner & Papst, San Francisco, Cal.; Geo. D. Bower, Trenton, N. J.; A. C. Harding, Chicago, Ill.; Fenlayson & Popkins, Detroit, Mich.; Joseph Mohr, Chicago, Ill.

Following is the text of the paragraphs of sections of rules amended in part only, the parts stricken out inclosed in brackets [thus], while the amendments to such paragraphs are printed in italics. Entirely new sections and paragraphs of sections are in plain type preceded by the word (new) in parenthesis.

An amendment to section 3 of Rule II, relating to strength of the longitudinal seams of boilers, failed to receive the approval of the Secretary of the Treasury.

JAS. A. DUMONT,

Supervising Inspector-General,

President of the Board of Supervising Inspectors of Steam Vessels. Approved, February 14, 1893.

CHARLES FOSTER,

Secretary of the Treasury.

RULE II.

Section 7. [Added to section.] (New.) Steel stay bolts exceeding a diameter of 11 inches and not exceeding a diameter of 2 inches at the bottom of the thread may be allowed a strain not exceeding 8,000 pounds per square inch of cross section; steel stay bolts exceeding a diameter of 24 inches at bottom of thread may be allowed a strain not exceeding 9,000 pounds per square inch of cross section; but no forged or welded steel stays will be allowed.

The ends of such stays may be upset to a sufficient thickness to allow for truing-up and including the depth of the thread.

And all such stays after being upset shall be thoroughly annealed.

All steel bars intended for use as stay bolts to be allowed a strain exceeding 6,000 pounds per square inch of cross section shall be tested by the inspectors, in lots not to exceed fifty bars, in the following manner: Inspectors shall promiscuously select one bar from each lot and bend one end of such bar cold to a curve the inner radius of which is to equal one and one-half times the diameter of the test bar; and should any such test bar break in the bending process, the lot from which the test bar was taken shall not be allowed to be worked into stay bolts for marine boilers.

And all manufacturers of marine boilers desiring to employ the steel stays provided for herein shall be required to furnish the inspectors with the following form of affidavit:

"STATE OF

of

"Personally appeared before me, a notary public for and in the county

who, being first duly sworn, of the steam boiler works

and that the lot or lots

of steel bars from which test bars were taken and tested by the inspector- on the

day of

189, and allowed for use in the

steam boiler- to be constructed for the steamer allowed a strain not to exceed

-, and to be

pounds per square inch of sec

tion as a working steam pressure, will be used in the construction of

quired to carry a strain equal to pounds per square inch of section will be used as stay bolts or stays in the construction of the boiler for the said steamer unless tested by the inspector and approved by him in accordance with the requirements of law.

"Sworn to and subscribed before me this

day of

189-.

"Notary Public."

Sections 8, 9, and all of that part of section 10 which precedes "corrugated furnace flues" were repealed.

RIVETED AND LAP-WELDED FLUES.

8. (New.) The following table shall include all riveted and lapwelded flues exceeding 6 inches in diameter and not exceeding 40 inches in diameter not otherwise provided for by law. And all such flues shall be made in sections, according to their respective diameters, not to exceed the lengths prescribed in the table, and such sections shall be properly fitted one into the other and substantially riveted, and the thickness of material required for any such flue of any given diameter shall in no case be less than the least thickness prescribed in the table for any such given diameter; and all such flues may be allowed the prescribed working steam pressure if in the opinion of the inspectors it is deemed safe to make such allowance. And inspectors are therefore required, from actual measurement of each flue, to make such reduction from the prescribed working steam pressure for any material deviation in the uniformity of the thickness of material, or for any material deviation in the form of the flue from that of a true circle, as in their judgment the safety of navigation may require.

.18-inch.

Table of steam pressure per square inch allowable on riveted and lap-welded flucs made in sections.

.23 .24 .25 .26

Thickness of material required.

.18

.20 .21

1

.27 .28 .29 .30 .31 .32 .33

inch. inch. inch. inch. inch. inch. inch. inch. inch. inch., inch. inch. inch. inch. inch. inch. inch.

Diameter of flues.

Lbs.

Lbs. Lbs.

Lbs.

Lbs.

Lbs.

Lbs.

Lbs.

Lbs.

Lbs.

Lbs.

Lbs.

Lbs. Lbs.

Lbs.

Lbs.

Lbs.

pres- pres- pres- pres- pres- pres- pres- pres- pres- pres- pres- pres- pres- pres- pres- pres- pres-
sure. sure. sure. sure. sure. sure. sure. sure. sure. sure. sure. sure. sure. sure. sure. sure. sure.
189

Thickness of material required.

Table of steam pressure per square inch allowable, etc.--Continued.

.34

.35

.36

.37 .38 .39 .40 .41.42 .43 .44 45 46 .47 .48 .49 .50 inch. inch. inch. inch. inch. inch. inch. inch, inch. inch. inch, inch, inch. inch, inch. inch. inch.

Diameter of flues.

Riveted and lap-welded flues of any thickness of material, diameter, and length of sections, prescribed in the table, may be made in sections of any desired length, exceeding the maximum length allowed by the table, by reducing the prescribed pressure in proportion to the increased length of section, according to the following rule:

RULE.-Multiply the pressure in the table allowed for any prescribed thickness of material and diameter of flue by the greatest length, in feet, of sections allowable for such flue, and divide the product by the desired length of sections, in feet, from center line to center line of rivets in the circular seams of such sections, and the quotient will give the working steam pressure allowable.

EXAMPLE.

Taking a flue in the table, 24 inches in diameter, required to be made in sections not exceeding 2.5 feet in length, and having a thickness of material of 0.44 of an inch, and allowed a pressure of 157 pounds and it is desired to make this flue in sections 5 feet in length. Then we have

THICKNESS OF MATERIAL REQUIRED FOR TUBES AND FLUES NOT OTHERWISE PROVIDED FOR.

9. (New.) Tubes and flues not exceeding 6 inches in diameter, and made of any required length; and

Lap-welded flues required to carry a working steam pressure not to exceed 60 pounds per square inch, and having a diameter not exceedgin 16 inches and a length not exceeding 18 feet; and

Lap-welded flues required to carry a steam pressure exceeding 60 pounds per square inch, and not exceeding 120 pounds per square inch, and having a diameter not exceeding 16 inches and a length not exceeding 18 feet, and made in sections not exceeding 5 feet in length, and fitted properly one into the other and substantially riveted; and All such tubes and flues shall have a thickness of material according to their respective diameters, as prescribed in the following table:

10. (New.) Lap-welded flues not exceeding 6 inches in diameter may be made of any required length without being made in sections.