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bee ne 8\ e cted, egg-shells have been found within, that havecanae ^ there by weasels.

wis ° * ee P t * le ^ oor from dampness, beams are laid length-lar * an< ^ to P reven t these beams from being soon rotten,^.Se stones are laid under them; these beams are eight oris h lnc ^ es ®<iuare, or rather ten high and eight broad, whichijj. tter > and eighteen inches distant from each other; their0Ver v ®iis filled with dry sea-coal, or chips of dry stones;hr r , t ^ ese beams are others laid crosswise, four inchesPlank ^ VC k*Sb> which are covered with two-inch

inst^ p e l' c l° r would have brick walls made under the floor,but tb beams, and a double floor laid on the cross-beams ;

ne plan above described is, we think, preferable.

'vinw ^' V . e bght to the magazine, a window is made in eachthi t’ w * l ich is shut up by two shutters of two or three inchesth e ’ ° n . e w ltbin and the other without it; that which is on^'th°'J tSl< ^ e * s covered with an iron plate, and is fastenedare b ° ts ’ as well as that on the inside. These windowsme tQa ^ e ver y high, for fear of accidents, and are opened byWeath a Mdder, to air to the magazine in fine dryTl Gr *

the lere ' s likewise a double door, made of strong planks,side° ne °P ens on the outside, and the other within ; the out-lock ft"** ' S a ' so covere( l with an iron plate, and both are°f by a strong double lock ; the store-keeper has the keyou»l,t 0u tside J and the governor that of the inside: the doorthe rJl face the south nearly, if possible, in order to render*n rr . ma = az ' ne as light as can be, and that the wind blowingi 3 a 7 be dry and warm. Sometimes a wall of ten feet hight 0 o r °und the magazine about twelve feet distant from it,kf r anything from approaching it without being seen,

meat -U 6r b as proposed some alterations, by way of improve-jf ! , ln hi. Vauban’s construction.

\v| 1 i c l i ar ? e magazines are required, the piers or side wallsfeet 1 0 8u PP ort the arch should be ten feet thick, seventy-twoBu Ppor'^' an< ^ twent y- five i® et high; the middle wall, which: higf, two sma H arches of the ground floor, eight feet

*blck n n< * e 'obteen inches thick, and likewise the arches: theand t|f SS t b e great arch should be three feet six inches,befor e 6 ® ount erforts, as well as the air-holes, the same asfortjg d Magazines of this kind should not be erected intbe ca t0Wns > but in some inland part of the country nearIt where no enemy is expected.arch es heen observed, that after the centres of semicircularbaug^hp' 6 s tfuck, they settle at the crown and rise up at theamended*’ now ’ as this shrinking of the arches must bethe Cem ' Vlt h ill consequences, by breaking the texture of'hg the • nt a ^ ter it has been partly dried, and also by open-ing to ° lntS °b the voussoirs at one end, Dr. Hutton pro-by the r ® me( ly this inconvenience, with regard to bridges,Sfeat 6r • rc ^ e quilibration ; and as the ill effect is much°f en u ;iPowder magazines, he also proposed to find an arche Pao j s ra tion for them also ; and to construct it when the'be $ ariie T. ent y feet, the pitch or height ten, which areY te rior ai ® ens ’ ons as those of the semicircle, the inclined, 8ht of?i, - S ’ at t0 P> forming an angle of 113°, and the,° s eveo f ' le * r an o u lar point above the top of the arch equal»y th e f> eet ’ 'his curious question was answered, in 1775,° u nd j n Mr. Wildbore, and the solution of it may beutton’s Miscellanea Mathematica.j °pd, j*ANY, the beautiful reddish - brown colouredj bj nat . u °h household furniture is now chiefly made.i*(. Ve . °f 'he warmest parts of America and the Westj n thrives in most soils in the tropical climates, butl b Q a x 'ur e . and grain according to the nature of theoc ks it is of a smaller size, but very hard and

weighty, of a close grain, and beautifully shaded; while theproduce of the low and richer lands is observed to be morelight and porous, of a paler colour, and open grain; and thatof mixed soils, to hold a medium of both.

The mahogany-tree is stated to be of very rapid growth,and makes a very fine appearance. Its trunk often exceeds40 feet in length, and 6 feet in diameter. The Honduras mahogany is cut down at two periods in the year; that is, atChristmas , and in the autumn ; the trees are cut off at about12 feet from the ground, the workmen having a stage towork upon. The trunk furnishes wood of the largest dimen-sions ; but, for ornamental purposes, the branches are prefer-able, the grain in them being closer, and the veins morevariegated. Mahogany was first brought to London in theyear 1724.

In a dry state, mahogany is very durable, and not subjectto worms. It does not last long when exposed to the weather.It is a kind of wood that would make excellent timbers forfloors, roofs, &c., but on account of its price its use is chieflyconfined to furniture and doors for rooms, for which purposesit is the material most in use. It is sometimes used for someparts of window-frames, and for sashes, but from its notstanding the weather well, it is not -so fit for these purposes.It has also been extensively used in the framing of machineryfor cotton-mills, &c.

The variety called Spanish mahogany, is imported fromCuba, Jamaica, Hispaniola, and some other of the WestIndia islands, and in smaller logs than the Honduras . Thesize of the logs is in general about 20 to 26 inches square,and about 10 feet in length. The Spanish mahogany is close-grained and hard, generally of a darker colour than Honduras ;free from black specks, and sometimes strongly figured; andits pores appear as if chalk had been rubbed into them.

The Honduras mahogany is imported in logs of a largersize, that is, from 2 to 4 feet square, and 12 or 14 feet inlength ; sometimes planks have been got 6 or 7 feet wide.The grain of the Honduras kind is generally very open, andoften irregular, with black or gray spots. The veins andfigures are frequently very fine and showy; the best kindis that which is most free from gray specks, and of a finegolden colour. It holds with glue better than any otherwood.

The cohesive force of a square inch of Spanish mahoganyis 7560 pounds, and of Honduras mahogany 11475 pounds.

The weight of the modulus of elasticity of mahogany, is1,255,500 pounds, for a square inch for Spanish ; and 4,593,000for Honduras . The weight of a cubic foot of mahogany isfrom 35 to 53 pounds. Representing the—

Strength of oak by 100, that of Span, mahog. is 67; of Honduras is 96.

Stiffness of oak by 100.73; .93.

Toughness of oak by 100.61; .99.

MAIN COUPLES. See Couples.

MALLET, (from the Latin malleus ) a large kind ofhammer, made of wood, much used by artificers who workwith a chisel, as stone-cutters, masons, carpenters, joiners, &c.

MANSARD ROOF . See Curb Roof. The word isderived from Mansart, the inventor .

MANSART, FRANCIS, an eminent French architect ,born at Paris in 1598, was son of the king’s carpenter, andreceived those instructions which led him to eminence as anarchitect, from the celebrated Gautier; but for the high rankto which he attained in his profession, he was indebted tothe force of his own genius. His taste and judgment, unitedwith a fertile imagination and sublime ideas, enabled him toequal the greatest masters in his plans ; he was, however, tooapt to alter his designs, and even, in aiming at perfection, todemolish what was already not only well done, but scarcely

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