The Royal Engineers Journal
Total Page:16
File Type:pdf, Size:1020Kb
THE ROYAL ENGINEERS JOURNAL. Vol. XVI. No. 3. SEPTEMBER, 1912. CONTENTS. ---- P<tle. 1. The Survey of Pemba. By Capt. J. E. E. CRASTER, R.E. (With Photos and Plat) 145 2. The Military Archology of Kent. By Major A. M. HENNIKER, R.E. (With Plates) ... .... ... ......... 3. An Engneer Omcer under Wellington in the Peninsula (continued).-Edited by Commander the Hon. HENRY N. SHORE, R.N., Retired ... ... .. 71 4. Memoir:-Lieut..General Sir Gordon Douglas Pritchard, K.C.B., Colonel Commandant, R.E. ... ... ... ... ... 183 5. Transcript:-Report on Artificial Illuminants, other than Electric, suitable for Barracks Workshops and Large Open Spaces.--(To bt continued). By Capt L. N. MALAN, R.E. (With Plait) . .. ... .. 187 6. Review:-The Story of erusalem. By Col. Sir C. M. WATSON, £.C.M.G., C.B., M.A., etc. Illustrated by GINEVIEVE WATSON. (E.H.H.) ... ... 20 7. Notices of Magazines '.... .. .. 203 S. Recent Publicatioes of Military Interest ... ... ... 209 Books 9. Reoeived... ... ... ... ... .. 21 INSTITUTION OF RE OFFICE COPY DO NOT REMOVE R.E. Institute Publications. The SOLE AGENTS for the Sale of the whole of the above are W. l J. MACKAY & Co., Ltd., Chatham, And to whom all but Members of the R.E. Institute should apply. THE Royal Engineers Journal Can now be obtained at Messrs. HUGH REES, Ltd., 5, Regent Street, S.W. G. E. CARRINGTON, For many years Master Tailor, Royal Engineers, TAILOR &MILITA R Y OUTFITTER, 53, HIGH STREET, OLD BROMPTON, KENT, And at CARLTON HOUSE, REGENT STREET, near Waterloo Place, S.W. HOURS OF BUSINESS:- Old BDrmpton, 8.30 to 7.30; Saturdays, 8.30 to 1. Oariten House, 11 to 6; Saturdays, 11 to 1. - - Telephone No.-East 53. Telegraphic Address:-" Constructive Ironworks, London." MATTW. T. SHAW & CO., Ltd., MILLWALL, LONDON, E. CONSTRUCTIONAL STEELWORK, FRAMED BUILDINGS, BRIDGES, ROOFS, Etc. I.arge Stocks of Joists, Channels, Antgles, Tees, Flats, Plates, Chequers, Rounds, Squares, Rivets, Bolts, (Galvanizcd Sheets, etc., etc. VERY PROMPT DELIVERIES GUARANTEED. A D I 'ER 7TSEMENTS. THE Goldsmiths &Silversmiths Company, Ltd. BY ROYAL WARRANT With hich is incorporl:ted The Goldsmiths Alliance, Ltd. (A. I1. ory&So S s), Establ;ihed 1751. Famous the World over for DESIGN. QUALITY. VALUE. "SERVICE" WATCH GUARANTEE-D. entlenns Keylesse len's Lever Watch, specially adapted for Military use, and constant hard-wear, in I)Dustproof and Airtight Case. WATCHES SENT ON APPROVAL. Illustrated Catalogue POST-FREE. TIHE PUBLIC SUPPLIED DIRECTAT MANUFACTURERS' CASII PRICES. THE "SERVICE" WATCH. IN OXIDISED STEEL CASE £2 10 0 112, RECENT ST., LONDON, W. IN SOLID SILVER CASE - £3 10 0 T OD. O IN 18-CARAT GOLD CASE - £12 0 0 . THE "PERFECTION" BRAst IT PoLT/ANDPATENT GLAZING. CLIP CAP 1 C |o Putta/ly. A o Pait/. Imperishable. RIVET j1' | ASBESTOS Steel Glazing Bars Galvanized or also entirely covered wilh lead to prevent corrosion. GUARANTEED WATERTIGHT. ONDENSATION EHELLIWELL&Co ,Ld. BYp.ou Extensively u ed by H.M. Government - for Barracks, Drill Halls. Dock Sheds. "ORDINARY" BAR. Post Offices, Stores, Etc. * AKTIENCESELLSCHAFT HAHN, CASSEL, Germany. ° SPECIALITY. Instruments of every description for TESTING ARMS AND EXPLOSIVES. Optical Instruments for Artillery. " Iahn " Telemeters for use in the Armty and Navy. E Agents:-PLUTTE SCHEELE & CO., Ltd., 18.19, Queenhithe, London, E.C. 9 * iO000HB *eO A D VERTISE 4IENTS. SPECIAL NOTICE. THE EXPANDED METAL CO., Limi, begs to bring to the notice of all those interested in Metal Lathings for Plasterwork the fact that it has been granted PATENT RIGHTS FOR A NEW PROCESS OF MANUFACTURE by which an IMPROVED Diamond Mesh EXPANDED METAL LATHING is produced, which will be sold at lower prices than the original Diamond Mesh Lathings. The new patent Lathing will be known under the trade name of "BB EXPANDED METAL" LATHING and its principal features are in. MESH.-Diamond shalp, \ \ \ shortway of mesh. WEIGHT.- BB.26 gauge, 3lbs. per yard super. BB.24gauge, l4lbs. per yard super. B13. 22 gauge, 4 ilbs. per yard super. SIZE OF SHEETS.-Standard size sheets only, 9 ft. by 2ft. PROTECTIVE COATING.- The Lathing i. coated with a mineral oil in process of manu- facture and is dipped once in Asphaltum paint before leaving the Works. SPACINGS.- The z6-gauge Lathing "BB. Expanded Metal" Lathing. may be used .t spacings up to 12 inches; the 24-gauge Lathing may be ACTULAI.SIZE OF MIESHES. used at spacings up to .5 inches; the Write for Price List and Samples. 22-gauge Lathing may be used at spacings up to 8iinches, for Horizontal and Sloping iwork, and for Vertical Expanded Metal Lathirgs are retailed b6Y work the above spacings may be in- ilferchantts on,ly. creased by 3 inches. Slocks are held in most larg,e centres. Head Office Works (to which address enquiries shLi,ud be srnt) (to rlhich address orders should be senti York Mansion, York Street, Siranton Works, WESTMINSTER. LONDON, S.W. WEST HARTLEPOOL. Telegrams:- "Distend." .oondon. Tlregra,s:-;- Ex.pansion," Itest larll/ePool. Telephon,es:-GerrardS19. ictoria 114. Telephones :--94 IestlIartlepool (2 lines). CONTENTS. PA(:I. I. TiIE SRVEY OF PEMBA. By Capt. J. E. 1E. Craster, R.E. (ilt'ih P/hotos and 'a ) ... .. ... .. ... ... ... ... ... ...... 14 5 2. THE MILITARY AIRCH1/EOI.OGY OF KENTI . By Major A. M. lenniker, R.E. (With Plates) ... ... ... ... ... ... .. .... 155 3. AN ENGINEER OFFICER UNDER WEI.LINGTON IN I'lE PENINSUI.A (contli/nued).- Edited by Commander the lion. Hlenry N. Shore, R.N., Retiled .. ... 171 4. MEMOIR :- Lieut.-General Sir Gordon Douglas Pritchard, K.C.I3., Colonel Commandant, R. E. ..... ... ... ... ... ........ .... 183 5. TIRANSCRIPT :- Report on \Atificial Illuminants, other than Electric, suitable for Ilaracks, Workshops and Large Open Spaces.-(To be cont[inued). By Capt. L. N. Malan, (IWith ;.E. Plate) ...... .......... .. 187 6. REVIEW :- The S.tosy of 7erusal,m. By Col. Sir C. M. Watson, K.C. r.G., C.lB., AM.A., etc. Illustia ed by Genevieve Watson. (E.H.II.) .. ..... 201 7. NOTICES OF MAGAZINES :- /KriegstechinischeZrtischrift. 1y Capt. C. Otley Place, D.s.o., R.E. ... 203 Rivista dii A;rtiiliera e Geiiio. By Col. Sir Edwd. T. Thackeray, v.c., K.C. I., late R. I'V............... ... .. ... 205 in , i... ... .. ........... ...... 20S S. RECENT PUBLICATIONS o1F M IIT.ARY INIERI.ST . ... ... .. ... 209 9. BOOKS RECEIVED ... ... .. ... ... ... .. ... ... ... 216 .Aulhors alaone ate ,esponsible for /ize sta(lelents madie and /he o/pinionst expressed inl llieir papers. The Survey of Pemba 192. 145 TIIE SURVEY OF PEMlBA. By CAPT. J. E. E. CRASTER, R.E. PEMBA is a coral island some 400 square miles in area, lying 60 miles north of Zanzibar, and forming part of the Zanzibar Protectorate. Upon it is grown more than half the world's total supply of cloves; a very valuable crop, upon which the Zanzibar Government levies an export duty of 25 per cent. The clove plantations, which cover about a quarter of the island, are owned by Arabs, who until the abolition of slavery in 1897 employed nothing but slave labour. It is said that in the flourishing days of the slave trade r4,ooo slaves a year were imported into Zanzibar and Pemba, of whom the majority died within a year or two. The natives of Pemba are closely allied to the Swahilis of Zanzibar, and speak a dialect of the Swahili language. There are also in the island a considerable number of freed slaves, who belong to nearly every tribe in East and Central Africa. CLIMATE. The temperature varies but little throughout the year. The minimum cold weather temperature at night is about 74° and the maximum day temperature in the hot weather 90°. Heavy rain falls throughout April and May, and there is a second rainy season in November. Showers are of almost daily occurrence during the other months of the year, and the air is always saturated with moisture. PRELIMINARY RECONNAISSANCE. In August, 19Io, Pemba was visited by Major Gordon, R.E., who made a report, and an estimate for the survey. In April, 1911, a survey party consisting of Capt. Craster, R.E., Lieut. Kyngdon, R.G.A., Lance-Corpls. Cager and Whitters, R.E., left England, and arrived in Pemba at the end of May. MEASUREMENT OF A BASE. The island is about 40 miles long, and 6 to 12 miles wide. Some 2 or 3 miles off the western coast lies a chain of small islands, and on the eastern shore of the largest of these a base had been selected by Major Gordon. Nearly the whole length of the base lay below high water mark, and the central portion below the low water mark of neap tides, so that the measurements could only be made at low water during spring tides. This involved a delay of Io days between I46 THE ROYAL ENGINEERS JOURNAL. [SEPTEMBER the first and second measurements. The measuring party were often working in water a foot, or more, in depth, but this caused little difficulty, and had the advantage of keeping the tape at a uniform temperature. The base was measured with a 300-ft. steel tape, and the end of each tape length was marked by a steel toilet pin stuck in the side of a wooden picket, driven firmly into the ground. The tape was stretched with a spring balance to a tension of 20 Ibs. This is as heavy a pull as can be conveniently applied by hand. If tapes longer than 300 ft. are used, a heavier pull is required, and it is desirable that some mechanical apparatus should be provided for applying it. The first measurement of the base, after making the necessary corrections for temperature, etc., gave a value of I3817-343 ft., and the second a value of I3817'232 ft.