Personet Hodie and  Tempus Transit Gelidum are simple tunes easily played on a recorder by even one such as I. 
Many thanks to Paul White for transcribing them for me.
Personet Hodie_1.jpg
This is an Xmas (or Easter depending on to whom you are speaking) carol. The orignal song as apparently from the 14th C, but the lyrics seem to alter over time. These ones match the tune that I have added.
Rather simple and echoes really well in a quiet valley.

Personet Hodie

1. On this day earth shall ring
with the song children sing
to the Lord, Christ our King,
born on earth to save us;
him the Father gave us.

Id-e-o-o-o, id-e-o-o-o,
Id-e-o gloria in excelsis Deo!

2. His the doom, ours the mirth;
when he came down to earth,
Bethlehem saw his birth;
ox and ass beside him
from the cold would hide him. Refrain
3. God's bright star, o'er his head,
Wise Men three to him led;
kneel they low by his bed,
lay their gifts before him,
praise him and adore him. Refrain

A quite upbeat song which I have previously seen an English translation. When I find it again I shall add it here. Which I have and I have. The song is a 13th century one about the coming of spring.
Tempus transit gelidum, mundus renovatur,
verque redit floridum, forma rebus datur.
Avis modulatur, modulans letatur,
avis modulatur, modulans letatur
lucidior et lenior aer iam serenatur;
iam florea, iam frondea silva comis densatur.
Ludunt super gramina virgines decore,
quarum nova carmina dulci sonant ore.
Annuunt favore volucres canore,
favet et odore tellus picta flore.
Cor igitur et cingitur et tangitur amore,
virginibus et avibus strepentibus sonore.
Tendit modo retia puer pharetratus;
cui deorum curia prebet famulatus,
cuius dominatus nimium est latus,
per hunc triumphatus sum et sauciatus:
pugaveram et fueram en primis reluctatus,
sed iterum per puerum sum Veneri prostratus.
Unam, huius vulnere saucius, amavi,
quam sub firmo federe michi copulavi.
fidem, quam iuravi, numquam violavi;
rei tam suavi totum mi dicavi.
Quam dulcia sunt basia puelle! iam gustavi:
nec cinnamum et balsamum esset tam dulce favi!
Tempus Transit Gelidum
The cold times pass, the world is renewed, the flowers and spring return.
The birds rejoice with pleasure, and the air is cheerful. Decorous maidens play on the grass, singing new songs from their sweet mouths, and joyfully the birds join in. The heart is touched by love, as girls and birds make music. Now the boy with the quiver spreads his nets -- by him was I conquered and wounded. At first, I fought and resisted, but the boy once again made me a subject of Venus. And, so injured, I fell in love. She has bound me with a strong bond, and to her I am devoted. How sweet are her kisses, sweeter t= han cinammon, or honey from the comb