aist OUTLINE SKETCH; OF RAINFALL INVESTIGATIONS FROM A.D. 1677 TO A.D. 1865, WITH A LIST OF ALL PLACES IN GREAT BRITAIN AND IRELAND AT WHICH OBSERVATIONS ARE KNOWN TO HAVE EVER BEEN MADE, A MAP SHOWING THE POSITION OF GAUGES NOW AT WORK. BY G. J. SYMONS, MEMBER OF THE BRITISH AND SCOTTISH METEOROLOGICAL SOCIETIES. [Fi-om the Report of the British Association for the Advancement of Science for 1865.] LONDON: PRINTED BY TAYLOR AND FRANCIS, RED LION COtTRT, FLEET STREET. 1866. A-vo PRESENTATION COPY. Mr. G. J. Symons has much pleasure in forwarding this extract from the British Association Beport for the current year, the Council of the Associa¬ tion having kindly granted the necessary number of copies. Mr. Symons trusts that every recipient will carefully examine the list of stations, point out any errors which can be detected, and try to fill up some of the many gaps which .now exist: for instance, Cumberland, White- haven, The Plosh, observations have been received from 1844 to 1853, from 1855 to 1861, and for 1863; the returns for 1854 and 1862 are missing; surely some one must have a copy of the fall in those years, and could send them, if they would or could hunt through their papers for them. Mr. Symons feels he has done his share in getting the 'list to its present state, and he now asks all the observers to help him. Let even one observer in each county make a point of examining the list of his own county, ascer¬ taining the observers' names where unknown, and, where these are given, making sure that no observations were made before or after the dates men¬ tioned : if so, the " C " and " T " can be added, and the entry will be com¬ plete. If, moreover, they will go through the files of their county papers, and the local books in their libraries, then indeed will the list be nearer perfection than it now is. It may save time and trouble, where the county (like Lancashire) is too large for the local knowledge of one person, for several observers to unite, and report collectively to Mr. Symons. But, at least, Mr. Symons hopes all will see that their own entry is correct, and that they will search through their meteorological papers for any returns not quoted herein, 136 Camden Road, London, N.W. 191036 ON THE RAINFALL OF THE BRITISH ISLES. In my previous reports on the progress of rainfall investigations I have scarcely referred to what had been done before I undertook the collection and organization to which I have now devoted nearly six years. I purpose to supply the omission on this present occasion, and to divide my Report into the following divisions :— 1. "What had been done prior to 1860. 2. What has been done since 1860. 3. What remains to he done. 4. A few particulars respecting the rainfall of the last fifty years, and the faU in 1864. 1. What had been done prior to 1860.—Having been almost wholly en¬ gaged during the past year in clearing up arrears, and in thoroughly classifying the materials hitherto collected, the imperative necessity of circulating amongst engineers, meteorologists, and rainfall observers a complete index of the collected observations has been brought prominently before me. I have therefore prepared such an index, and annexed it to this Report. Resides its general usefulness, it will he specially so in two respects. (1) Every station, whether discontinued or not, being entered, with the years between which observations have been obtained, and with observer's name, and height above n sea-level, any one, whether engineer, agriculturist, or physicist, can ascer¬ tain with the greatest ease exactly what observations have hitherto been col¬ lected. In order to facilitate reference, the stations are arranged alphabetically in counties; and there are also provided general indices of England and "Wales, Scotland, and Ireland. (2) Those who are willing to help on the completion of the collection will see at once what I have, and what I have not; and thereby they will be saved much needless copying and I much corre¬ spondence. A barren index, however, throws little light on the history of rainfall in¬ vestigations. Before entering on this I desire to meet at the very outset an objection sometimes raised., viz., that we cannot trust very old observations, and therefore 1 may be busy collecting useless materials. I maintain that we can trust them, and have the pleasure of knowing that my friend llr. Glaisher fully agrees with me on this point. I think them far more reliable than many modern ones; for in the 17th and early part of the 18th century, to measure the fall of rain was esteemed a serious undertaking, only to be accomplished by first-class men. The repeated reference to the height of their gauges, their diameter, and the number of pounds and ounces troy cor¬ responding to an inch of rain over the area of the "tunnel" of their gauges, and the details frequently given, combine to render it certain that they took every reasonable precaution to secure accuracy. The results they obtained, and which they would hardly credit, we of the 19th century know to be just what Avas due to the situation of the gauges. Another point to be remem¬ bered is this, it is not intended to use any old observations in determining the absolute mean fall at any place, or, in other words, in determining the geo¬ graphical distribution of rain; that will be done from recent observations with tested instruments. The old observations will only be used for determining the existence or otherwise of secular variation, and for that purpose an in¬ accurate gauge would do as well as a perfect one. The earliest observations I have yet obtained are those of Mr. Townley, of Townley in Lancashire, extending (with two intervals) from a.d. 1677 to 1705, or twenty-eight years. Mr. Townley believed his to be the first made in England; I do not feel sure that they were so. The only other observer in the 17th century whose observations have yet been obtained was the Eev. AY. Derham, of Upminster, near Itomford in Essex, who began in March 1696, and has left a series of yearly totals (months also for some years) for nine¬ teen years. The longest and most perfect record at present obtained was kept by Thomas Barker, Esq., of Lyndon in Butland; it extends from 1736 to 1794, or fifty-nine years. It is doubtful if so long a record will ever again be kept by one person, with one gauge and without interruption. Erom Table I. it will readily be seen how sudden and great has been the increase of observers during the last thirty years, and especially during the last five, in which one finds the results of the recent grants of this Associa¬ tion. Erom 1677 to 1800 the returns never number more than twenty-six per annum, and averaged only four; and in subsequent ten-yearly periods the numbers average up to 1810, 15; to 1820, 21; to 1830, 40; to 1840, 103; to 1850, 178; to 1860, 366; and at the present time number rather more than a thousand. It is right to mention that no records have yet been ob¬ tained for 1687 and 1688, 1694 to 1696, 1717 to 1721,1724 and 1725, since which time there is no year without one or more complete registers. That is to say, rain records go back complete 140 years, and with intervals about fifty years more, or 200 years altogether. Table I. Number of Records obtained for each year from 1677 to 1864, Number. Number. 1 — 0) rz — 0) c o ^ O PH Year. cS # 2 [rt Y'ear. rt 2 [rt -C ju c '5 TJ «« rd s *5 c3(S rass • •""* c cacie cS C3 C r-; ae rt "rt <u 5 S C S o -2 g 5 CJo 'a o W m t—ii1 H w CO t—i E- 1677. 1 1 1720. 1678. 1 1 1721. 1679. 1 1 1722. 1 1 3 1723. 1 1 1680. 1 1 1724. 1681. 1 1 1725. 1682. 1 1 1726. 1 1 1683. 1 1 1727. 1 . 1 1684. 1 1 1728. 1 . 1 1685. 1 1 1729. 3 . , 3 1686. 1 1 8 1687. 1730. 3 3 1688. 1731. 3 1 4 1639. 1 1 1732. 4 1 5 OQ 1733. 4 1 5 1690. 1 1 1734. 5 1 6 1691. 1 1 1735. 4 1 5 1692. 1 1 1736. 2 2 1693. 1 1 1737. 2 2 1694. , , . , 1738. 2 2 1695. 1739. 2 2 1696. 36 1697. 2 2 1740. 1 1 1698. 2 2 1741. 1 1 1699. Ji 2 1742. 1 1 10 1743. 1 1700. +J 2 1744. 1 1 1701. £ 2 1745. 1 1 1702. Ji 2 1740. 1 1 1703. 2 1747. 1 1 1704. 1 1 1748. 1 1 1705. 1 1 1749. 2 2 1706. 1 1 . 11 1707. 1 1 1750. 2 2 1708. 1 1 1751. 2 2 1709. 1 1 1752. 2 2 14 1753. 2 2 1710. 1 1 1754. 2 2 1711. 1 1 1755. 2 2 1712. 1 1 1756. 2 2 1713. 1 1 1757. 2 2 1714. 1 1 1758. 2 2 1715. 1 1 1759. 2 2 1716. I 20 1717. 1760. 2 2 1718. 1761. 2 2 1719. 1762. 3 3 - 7 1763. 1 1 b 2 Table I.