Chapter 10

The last sketch represents their first meal on board after a fast of thirty hours. Apple melons were chopped up for them by their "steward," who was to accompany them to Australia. It was curious to see a bird swallow a great lump and then to watch the lump working slowly down the animal's long neck. On the voyage they would be fed with maize or mealies, onions, apple melons, and barley. They require very little water; however, there were five large iron tanks on board in case they would feel thirsty. Our engravings are from sketches by Mr. Dennis Edwards, of Hoff Street, Capetown,

* * * * *

A NEW WEATHERCOCK.

An ordinary weathercock provided with datum points may, in the majority of cases, suffice for the observation of the wind during the day; but recourse has to be had to different means to obtain an automatic transmission of the indications of the vane to the inside of a building. The different systems employed for such a purpose consist of gearings, or are accompanied by a friction that notably diminishes the sensitiveness of the apparatus, especially when the rod has to traverse several stories. Mr. Emile Richard, inspector of the Versailles waterworks, has just devised an ingenious system which, while considerably reducing the weight of the movable part, allows the weathercock to preserve all its sensitiveness. This apparatus consists of two principal parts--one fixed and the other movable. The stationary part is designated in the accompanying figure by the letters A and B and by cross-hatchings. This forms the rod or support. An iron tube, T, with clamps, P, at its lower extremity forms the base of the apparatus, and is hidden, after the mounting of the apparatus, by the ornamental zinc covering, Z. The upper part of the tube carries a shoulder-piece, upon which rests a bronze platform, E, and which is slightly inclined outwardly to prevent the accumulation of water on it. Over the platform there move three crystal balls, which are held and guided by a horizontal disk movable around the stationary tube.

The movable portion, designed to receive the action of the wind and to indicate its direction, is designated by the letters C D and coarse lines. It consists of (1) a zinc tube, K, provided at intervals with copper rings, and entering the rod, A B, which serves as a guide for it; (2) of a bronze disk covered by an external ornament, O, fixed to the tube and resting on the balls; (3) of the vane, G, properly so called; and (4) of the cap, C, provided with bayonet catch, crowning the tube and covering the point of attachment of the wire of transmission. This latter consists of a simple brass or galvanized iron wire, f f, perfectly taut, and made fast in the top of the tube. After traversing as many stories as necessary this wire terminates, in the interior of the room where the observations are made, in a copper rod to which is fastened a horizontal arrow, F. The wire traverses the floorings through small zinc tubes; and, in the rooms through which it passes, it is protected by iron tubes. To the ceiling of the observing room there is affixed a wind-rose, R, on which the arrow reproduces all the motions of the vane.

This apparatus is now in operation in the different stations that the Versailles waterworks has established near the reservoirs of the plateau of Trappes, and it is also installed in several primary normal schools, where it is giving very good results.--_La Nature_.

* * * * *

CHARRED CLOVER.

A correspondent of the _Ohio Farmer_ reports an experiment in curing clover, showing how he just missed breeding fire in his barn, and illustrating the importance of ventilating hay mows:

In 1861 I used a horse fork for the first time. The haying season was not a bright one, and our clover was drawn a little greener than usual, and went into the mow in large and compact forkfuls. The result was intense heating, and consequently very rapid evaporation and sweating of the mow. On a bay holding ordinarily twenty tons we put at least thirty tons, as every load at the top seemed to make room for another. The barn was rather open, which allowed quite free evaporation on all sides as well as at the top. The result was that I had very bright and excellent hay at the bottom, top, and sides of that mow, but severals tons in the center were as completely charred as though burned in a coal pit. What prevented combustion has always been a mystery to me. Since that escape from a conflagration, I have not deemed it prudent to put clover in so green as to cause intense heating, or to fill a mow too rapidly. If we haul six loads per day to one mow, weighing thirty hundred each, which will shrink during the sweating process to one ton each, we have three tons of water to be thrown off by evaporation.

If we continue to put on six loads per day until the mow is full, the principal part of that moisture must rise through the entire mass. To relieve the hay of moisture, I deem it best to have several places of storage, and change daily or semi-daily from one to the other, thus giving time for a share of the moisture to pass off. To facilitate this evaporation and prevent the hay from reabsorbing it and becoming musty, the best of ventilation is necessary. Ventilation above a clover mow is as necessary as it is above a sugar or fruit evaporator. If there is not open space and draught sufficient to carry away the moisture, it is returned to the mow, and mould is the inevitable result. No ordinary amount of drying will prevent hay from becoming musty if ventilation is shut off during the sweating process. If a hole is cut through the floor at the bottom of the mow near the center and under a ventilator in the roof and a barrel placed over it and drawn up as the hay is mowed in, thus leaving a hole from bottom to top, evaporation will be facilitated and the quality of the hay improved. Salt thrown on, as the clover is put in, to the amount of two or three quarts to the ton, will make it a relish with stock.

* * * * *

THE QUEEN VICTORIA CENTURY PLANT.

(_Agave victoriæ-reginæ_.)

This beautiful Agave is now in blossom in the garden here, and I am happy to be able to send you photographs of it. This is the first time it has ever blossomed in cultivation, and it has never been seen in flower in a wild state. It is a mature native-grown specimen, dense in habit, and perfectly semi-spherical in form, and the leaves are arranged in spiral fashion with as much regularity as those of a screw pine. The circumference of the plant is 5 ft. 1 in., and it has 268 leaves. Its flower-stem appeared about the middle of June, grew rather fast till it was 7 ft. high, then rather slowly till it reached its full development. The scape is now 10 ft. 4 in. high above the plant, 6½ in. in circumference at the base, or 5¼ in. at a foot above the base; from there it tapers very gradually till near the apex. The flower-spike is exceedingly dense, and 5 ft. 8 in. long; the lower or naked portion, 4 ft. 8 in. long, is prominently marked by abortive flower buds, with, near the base, some bristle-like scales 3½ in. to 4 in. long. The flowers are regularly arranged in parcels of three, all the three being equal in size and opening together; they are greenish white in color, 1½ in. long, or, including the stamens, some 2¾ in. to 3 in. long.

The first flowers opened on August 3, and they have continued to open in succession, a belt about 3 in. wide opening each day. They remain in good condition for two days; on the third day the stamens wilt and drop down, but the pistil remains erect till the fourth day. On the first day of opening the pistil is not so long as the stamens by ¾ in.; on the second it has grown to be as long as the stamens, but it is not in condition to receive the pollen till after noon of the second day. Although the flowers on some eighteen inches of the spike have already blossomed, none of the ovaries have been fertilized; they are dropping off, but I am rather sanguine regarding those about the middle of the spike. So great is the superfluity of nectar contained in the flowers, that on the afternoon of the second day it often drops from the cups, and the least shake to the scape brings it down in a shower. The main beauty of the inflorescence consists in the dense bottle-brush-like mass of bright yellow anthers. This plant, together with several smaller ones, was contributed to this garden by Dr. Edward Palmer, who collected them in their native wilds--the mountains of Northern Mexico--some three years ago. He found them growing in a limited and rather inaccessible locality in gravelly and rocky soil some miles from Monterey. In addition to those he sent here he also sent a quantity to the garden of the Agricultural Department at Washington, and some to Dr. Engelmann, the eminent botanist at St. Louis. To Dr. Engelmann he also sent a piece of an old flower stem and some dried capsules which he found upon an old plant, and it was from these specimens in 1880 that the doctor was enabled to describe for the first time the inflorescence of this Agave.--_The Garden_.

* * * * *

ON THE CONSTITUTION OF THE NATURAL FATS.

By J. ALFRED WANKLYN and WILLIAM FOX.

In the course of an investigation in which we are at present engaged we have arrived at some results which appear to us to be very interesting. We find that the generally received view that the fats are ethers of glycerin is partially correct, and that instances of a different kind of structure occur among the natural oils and fats.

Ethers of iso-glycerin, or of homologues of iso-glycerin, appear to occur. Iso-glycerin has this structure:

C(OH)_{2} CH CH_{3}

It exists in its ethers, but cannot be isolated, and should be resolved into:

COOH + H_{2}O CH_{2} CH_{3}

Ethers of iso-glycerin, or ethers of homologues of iso-glycerin, yield no glycerin when saponified.--_Chemical News_.

* * * * *

A catalogue, containing brief notices of many important scientific papers heretofore published in the SUPPLEMENT, may be had gratis at this office.

* * * * *

THE SCIENTIFIC AMERICAN SUPPLEMENT.

PUBLISHED WEEKLY.

TERMS OF SUBSCRIPTION, $5 A YEAR.

Sent by mail, postage prepaid, to subscribers in any part of the United States or Canada. Six dollars a year, sent, prepaid, to any foreign country.

All the back numbers of THE SUPPLEMENT, from the commencement, January 1, 1876, can be had. Price, 10 cents each.

All the back volumes of THE SUPPLEMENT can likewise be supplied. Two volumes are issued yearly. Price of each volume, $2.50, stitched in paper, or $3.50, bound in stiff covers.

COMBINED RATES--One copy of SCIENTIFIC AMERICAN and one copy of SCIENTIFIC AMERICAN SUPPLEMENT, one year, postpaid, $7.00.

A liberal discount to booksellers, news agents, and canvassers.

MUNN & CO., PUBLISHERS,

261 BROADWAY, NEW YORK, N. Y.

* * * * *

PATENTS.

In connection with the SCIENTIFIC AMERICAN, Messrs. MUNN & Co. are Solicitors of American and Foreign Patents, have had 38 years' experience, and now have the largest establishment in the world. Patents are obtained on the best terms.

A special notice is made in the SCIENTIFIC AMERICAN of all Inventions patented through this Agency, with the name and residence of the Patentee. By the immense circulation thus given, public attention is directed to the merits of the new patent, and sales or introduction often easily effected.

Any person who has made a new discovery or invention can ascertain, free of charge, whether a patent can probably be obtained, by writing to MUNN & Co.

We also send free our Hand Book about the Patent Laws, Patents, Caveats. Trade Marks, their costs, and how procured, with hints for procuring advances on inventions. Address

MUNN & CO., 261 BROADWAY, NEW YORK.

Branch Office, cor. F and 7th Sts., Washington, D. C.